
Inputs to GAMESS
This page has the contents of the file "INPUT.DOC", that we
get with GAMESS and it resides in /usr/local/apps/gamess.It
describes the input to GAMESS. The section is written in a
reference, rather than tutorial fashion. However, there are
frequent reminders that more information can be found on a particular
input group, or type of calculation, in the 'Further Information'
section of this manual. There are also a number of
examples shown in the 'Input Examples' section.
It is useful to note that this chapter of the manual
can be searched online by means of the "gmshelp" command,
if your computer is of the Unix type. A command such as
"gmshelp scf" will display the $SCF input group. With no
arguments, the gmshelp command will show you all input
group names. Type "q" to exit the pager, and note that
some pagers will let you back up by means of "b".
The order of this section is chosen to approximate the
order in which most people prepare their input ($CONTRL,
$BASIS/$DATA, $GUESS, and so on). The next pages contain a
list of all possible input groups, in the order in which
they can be found in this section. The PDF version of this
file contains an alphabetized index of all group names at
the end.
*
name function module:routine
  
Molecule, basis set, wavefunction specification:
$CONTRL chemical control data INPUTA:START
$SYSTEM computer related options INPUTA:START
$BASIS basis set INPUTB:BASISS
$DATA molecule, geometry, basis set INPUTB:MOLE
$ZMAT internal coordinates ZMATRX:ZMATIN
$LIBE linear bend coordinates ZMATRX:LIBE
$SCF HFSCF wavefunction control SCFLIB:SCFIN
$SCFMI SCFMI input control data SCFMI :MIINP
$DFT density functional theory DFT :DFTINP
$MP2 2nd order MollerPlesset MP2 :MP2INP
$CIS singly excited CI CISGRD:CISINP
$CISVEC vectors for CIS CISGRD:CISVRD
$CCINP coupled cluster input CCSDT :CCINP
$EOMINP equation of motion CC EOMCC :EOMINP
$MOPAC semiempirical specification MPCMOL:MOLDAT
$GUESS initial orbital selection GUESS :GUESMO
$VEC orbitals (formatted) GUESS :READMO
$MOFRZ freezes MOs during SCF runs EFPCOV:MFRZIN
Note that MCSCF and CI input is listed below.
Potential energy surface options:
$STATPT geometry search control STATPT:SETSIG
$TRUDGE nongradient optimization TRUDGE:TRUINP
$TRURST restart data for TRUDGE TRUDGE:TRUDGX
$FORCE hessian, normal coordinates HESS :HESSX
$CPHF coupledHartreeFock options CPHF :CPINP
$MASS isotope selection VIBANL:RAMS
$HESS force constant matrix (formatted) HESS :FCMIN
$GRAD gradient vector (formatted) HESS :EGIN
$DIPDR dipole deriv. matrix (formatted) HESS :DDMIN
$VIB HESSIAN restart data (formatted) HESS :HSSNUM
$VIB2 HESSIAN restart data (formatted) HESS :HSSFUL
$IRC intrinsic reaction coordinate RXNCRD:IRCX
$VSCF vibrational anharmonicity VSCF :VSCFIN
$VIBSCF VSCF restart data (formatted) VSCF :VGRID
$DRC dynamic reaction path DRC :DRCDRV
$GLOBOP Monte Carlo global optimization GLOBOP:GLOPDR
$GRADEX gradient extremal path GRADEX:GRXSET
$SURF potential surface scan SURF :SRFINP
Interpretation, properties:
$LOCAL localized molecular orbitals LOCAL :LMOINP
$TWOEI J,K integrals (formatted) LOCCD :TWEIIN
$TRUNCN localized orbital truncations EFPCOV:TRNCIN
$ELMOM electrostatic moments PRPLIB:INPELM
$ELPOT electrostatic potential PRPLIB:INPELP
$ELDENS electron density PRPLIB:INPELD
$ELFLDG electric field/gradient PRPLIB:INPELF
$POINTS property calculation points PRPLIB:INPPGS
$GRID property calculation mesh PRPLIB:INPPGS
$PDC MEP fitting mesh PRPLIB:INPPDC
$MOLGRF orbital plots PARLEY:PLTMEM
$STONE distributed multipole analysis PRPPOP:STNRD
$RAMAN Raman intensity RAMAN :RAMANX
$ALPDR alpha polar. der. (formatted) RAMAN :ADMIN
$NMR NMR shielding tensors NMR :NMRX
$MOROKM Morokuma energy decomposition MOROKM:MOROIN
$FFCALC finite field polarizabilities FFIELD:FFLDX
$TDHF time dependent HF NLO properties TDHF :TDHFX
Solvation models:
$EFRAG effective fragment potentials EFINP :EFINP
$FRAGNAME specific named fragment pot. EFINP :RDSTFR
$FRGRPL interfragment repulsion EFINP :RDDFRL
$PRTEFP simplified EFP generation EFINP :PREFIN
$DAMP EFP multipole screening fit CHGPEN:CGPINP
$DAMPGS initial guess screening params CHGPEN:CGPINP
$PCM polarizable continuum model PCM :PCMINP
$PCMGRD PCM gradient contrl PCMCV2:PCMGIN
$PCMCAV PCM cavity generation PCM :MAKCAV
$TESCAV PCM cavity tesselation PCMCV2:TESIN
$NEWCAV PCM escaped charge cavity PCM :DISREP
$IEFPCM PCM integral equation form. data PCM :IEFDAT
$PCMITR PCM iterative IEF input PCMIEF:ITIEFIN
$DISBS PCM dispersion basis set PCMDIS:ENLBS
$DISREP PCM dispersion/repulsion PCMVCH:MORETS
$SVP Surface Volume Polarization model SVPINP:SVPINP
$SVPIRF reaction field points (formatted) SVPINP:SVPIRF
$COSGMS conductorlike screening model COSMO :COSMIN
$SCRF self consistent reaction field SCRF :ZRFINP
Integral, and integral modification options:
$ECP effective core potentials ECPLIB:ECPPAR
$MCP model core potentials MCPINP:MMPRED
$RELWFN scalar relativistic integrals INPUTB:RWFINP
$EFIELD external electric field PRPLIB:INPEF
$INTGRL 2e integrals INT2A :INTIN
$FMM fast multipole method QMFM :QFMMIN
$TRANS integral transformation TRANS :TRFIN
Fragment Molecular Orbital method:
$FMO define FMO fragments FMOIO :FMOMIN
$FMOPRP FMO properties and convergers FMOIO :FMOPIN
$FMOXYZ atomic coordinates for FMO FMOIO :FMOXYZ
$OPTFMO input for special FMO optimizer FMOGRD:OPTFMO
$FMOLMO localized MO for FMO boundaries FMOIO :FMOLMO
$FMOBND FMO bond cleavage definition FMOIO :FMOBON
$FMOENM monomer energies for FMO restart FMOIO :EMINOU
$FMOEND dimer energies for FMO restart FMOIO :EDIN
$OPTRST OPTFMO restart data FMOGRD:RSTOPT
$GDDI group DDI definition INPUTA:GDDINP
MCSCF and CI wavefunctions, and their properties:
$CIINP control over CI calculation GAMESS:WFNCI
$DET determinant full CI for MCSCF ALDECI:DETINP
$CIDET determinant full CI ALDECI:DETINP
$GEN determinant general CI for MCSCF ALGNCI:GCIINP
$CIGEN determinant general CI ALGNCI:GCIINP
$ORMAS determinant multiple active space ORMAS :FCINPT
$GCILST general CI determinant list ALGNCI:GCIGEN
$SODET determinant second order CI FSODCI:SOCINP
$DRT GUGA distinct row table for MCSCF GUGDRT:ORDORB
$CIDRT GUGA CI (CSF) distinct row table GUGDRT:ORDORB
$MCSCF control over MCSCF calculation MCSCF :MCSCF
$MRMP MRPT selection MP2 :MRMPIN
$DEMRPT det. multireference pert. theory DEMRPT:DMRINP
$MCQDPT CSF multireference pert. theory MCQDPT:MQREAD
$CISORT GUGA CI integral sorting GUGSRT:GUGSRT
$GUGEM GUGA CI Hamiltonian matrix GUGEM :GUGAEM
$GUGDIA GUGA CI diagonalization GUGDGA:GUGADG
$GUGDM GUGA CI 1e density matrix GUGDM :GUGADM
$GUGDM2 GUGA CI 2e density matrix GUGDM2:GUG2DM
$LAGRAN GUGA CI Lagrangian LAGRAN:CILGRN
$TRFDM2 GUGA CI 2e density backtransform TRFDM2:TRF2DM
$TRANST transition moments, spinorbit TRNSTN:TRNSTX
* this column is more useful to programmers than to users.
==========================================================
$CONTRL group (optional)
This group specifies the type of wavefunction, the type of
calculation, use of core potentials, spherical harmonics,
and similar fundamental job control options.
Note that this group's name contains only one letter "oh"
to conform with the 6 character maximum in any group name.
SCFTYP specifies the selfconsistent field
wavefunction. You may choose from
= RHF Restricted Hartree Fock calculation
(default)
= UHF Unrestricted Hartree Fock calculation
= ROHF Restricted open shell HartreeFock.
(high spin, see GVB for low spin)
= GVB Generalized valence bond wavefunction
or OCBSE type ROHF. (needs $SCF input)
= MCSCF Multiconfigurational SCF wavefunction
(this requires $DET or $DRT input)
= NONE indicates a single point computation,
rereading a converged SCF function.
This option requires that you select
CITYP=ALDET, ORMAS, FSOCI, GENCI, or
GUGA, requesting only RUNTYP=ENERGY or
TRANSITN, and using GUESS=MOREAD.
The treatment of electron correlation for the above SCF
wavefunctions is controlled by the keywords MPLEVL, CITYP,
and CCTYP contained in this group, or DFTTYP which is given
in $DFT. Obviously, at most one of MPLEVL, CITYP, CCTYP,
or DFTTYP may be chosen in any given run.
MPLEVL = chooses MollerPlesset perturbation
theory level, after the SCF. See the
$MP2 group (or $MRMP for MCSCF).
= 0 skip the MP computation (default)
= 2 perform second order energy correction.
MP2 (MBPT(2)) is only implemented for RHF, UHF, ROHF, and
MCSCF wavefunctions. Gradients are available for RHF, UHF,
or ROHF based MP2, but for MCSCF, you must choose numerical
derivatives to use any RUNTYP other than ENERGY, TRUDGE,
SURFACE, or FFIELD.
CITYP = chooses CI computation after the SCF,
for any SCFTYP except UHF.
= NONE skips the CI. (default)
= CIS single excitations from a SCFTYP=RHF
reference, only. This is for the
treatment of excited states, with
analytic nuclear gradients available.
See the $CIS input group.
= ALDET runs the Ames Laboratory determinant
full CI package, requiring $CIDET
input. Use with RUNTYP=ENERGY only.
= ORMAS runs an Occupation Restricted Multiple
Active Space determinant CI. The input
is $CIDET and $ORMAS.
= FSOCI runs a full second order CI using
determinants, with RUNTYP=ENERGY only.
The input is $CIDET and $SODET.
= GENCI runs a determinant CI program that
permits arbitrary specification of
the determinants, requiring $CIGEN
input. Use with RUNTYP=ENERGY only.
= GUGA runs the Unitary Group CI package,
which requires $CIDRT input.
Gradients are available only for RHF,
so for other SCFTYPs, you may choose
only RUNTYP=ENERGY, TRUDGE, SURFACE,
FFIELD, TRANSITN.
CCTYP chooses a CoupledCluster (CC calculation for the
ground state and, optionally, Equation of Motion
CoupledCluster (EOMCC) computation for excited
states, both performed after SCF (SCFTYP=RHF only).
See also the $CCINP and $EOMINP groups.
= NONE skips CC computation (default).
= LCCD perform a coupledcluster calculation
using the linearized coupledcluster
method with double excitations.
= CCD perform a CC calculation using the
coupledcluster method with doubles.
= CCSD perform a CC calculation with both
single and double excitations.
= CCSD(T) in addition to CCSD, the noniterative
triples corrections are computed, giving
standard CCSD[T] and CCSD(T) energies.
= RCC in addition to all CCSD(T) calculations,
compute the renormalized RCCSD[T] and
RCCSD(T) energies.
= CRCC in addition to all RCC calculations,
the completely renormalized CRCCSD[T]
and CRCCSD(T) energies are computed.
= CCSD(TQ) in addition to all RCC calculations,
noniterative triple and quadruple
corrections are used, to give CCSD(TQ)
and various RCCSD(TQ) energies.
= CRCC(Q) in addition to all CRCC and CCSD(TQ)
calculations, the CRCCSD(TQ) energies
are obtained.
= EOMCCSD in addition to a CCSD ground state,
excited states are calculated using the
equation of motion coupledcluster
method with singles and doubles.
= CREOM in addition to the CCSD and EOMCCSD,
noniterative triples corrections to CCSD
groundstate and EOMCCSD excitedstate
energies are found, using completely
renormalized CREOMCCSD(T) approaches.
Any publication describing the results of CC calculations
obtained using GAMESS should give reference to
P. Piecuch, S.A. Kucharski, K. Kowalski, and M. Musial,
Comput.Phys. Commun., 149, 7196 (2002)
Any publication describing the results of ground and/or
excited state EOMCC or CREOMCCSD(T) calculations obtained
using GAMESS must reference the above paper, as well as:
K. Kowalski and P. Piecuch,
J. Chem. Phys. 120, 17151738 (2004)
Analytic gradients are not available, so use CCTYP only for
RUNTYP=ENERGY, TRUDGE, SURFACE, or maybe FFIELD.
Generally speaking, the Renormalized energies are obtained
at similar cost to the standard values, while Completely
Renormalized energies cost twice the time. For usage tips
and more information about resources on the various Coupled
Cluster methods, see Section 4, 'Further Information'.
RELWFN = NONE (default) See also the $RELWFN input group.
= DK DouglasKroll transformation, available at
the 1st, 2nd, or 3rd order
= RESC relativistic elimination of small component,
the method of T. Nakajima and K. Hirao,
available at 2nd order only
= NESC normalised elimination of small component,
the method of K. Dyall, 2nd order only
* * * * *
RUNTYP specifies the type of computation, for
example at a single geometry point:
= ENERGY Molecular energy. (default)
= GRADIENT Molecular energy plus gradient.
= HESSIAN Molecular energy plus gradient plus
second derivatives, including harmonic
harmonic vibrational analysis. See the
$FORCE and $CPHF input groups.
multiple geometry options:
= OPTIMIZE Optimize the molecular geometry using
analytic energy gradients. See $STATPT.
= TRUDGE Nongradient total energy minimization.
See groups $TRUDGE and $TRURST.
= SADPOINT Locate saddle point (transition state).
See the $STATPT group.
= IRC Follow intrinsic reaction coordinate.
See the $IRC group.
= VSCF Compute anharmonic vibrational
corrections (see $VSCF)
= DRC Follow dynamic reaction coordinate.
See the $DRC group.
= GLOBOP Monte Carlo global optimization.
See $GLOBOP.
= OPTFMO genuine FMO geometry optimization using
nearly analytic gradient (see $OPTFMO).
= GRADEXTR Trace gradient extremal.
See the $GRADEX group.
= SURFACE Scan linear cross sections of the
potential energy surface. See $SURF.
single geometry property options:
= PROP Properties will be calculated. A $DATA
deck and converged $VEC group should be
input. Optionally, orbital localization
can be done. See $ELPOT, etc.
= RAMAN computes Raman intensities, see $RAMAN.
= NMR NMR shielding tensors for closed shell
molecules by the GIAO method. See $NMR.
= MOROKUMA Performs monomer energy decomposition.
See the $MOROKM group.
= TRANSITN Compute radiative transition moment or
spinorbit coupling. See $TRANST group.
= FFIELD applies finite electric fields, most
commonly to extract polarizabilities.
See the $FFCALC group.
= TDHF analytic computation of time dependent
polarizabilities. See the $TDHF group.
= MAKEFP creates an effective fragment potential.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Note that RUNTYPs which require the nuclear gradient are
GRADIENT, HESSIAN, OPTIMIZE, SADPOINT,
GLOBOP, IRC, GRADEXTR, and DRC
These are efficient with analytic gradients, which are
available only for certain CI or MP2 calculations, but no
CC calculations, as indicated above. See NUMGRD.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * *
NUMGRD Flag to allow numerical differentiation
of the energy. Each gradient requires
the energy be computed twice (forward
and backward displacements) along each
totally symmetric modes. It is thus
recommended only for systems with just a
few symmetry unique atoms in $DATA.
The default is .FALSE.
EXETYP = RUN Actually do the run. (default)
= CHECK Wavefunction and energy will not be
evaluated. This lets you speedily
check input and memory requirements.
See the overview section for details.
Note that you must set PARALL=.TRUE.
in $SYSTEM to test distributed memory
allocations.
= DEBUG Massive amounts of output are printed,
useful only if you hate trees.
= routine Maximum output is generated by the
routine named. Check the source for
the routines this applies to.
* * * * * * *
ICHARG = Molecular charge. (default=0, neutral)
MULT = Multiplicity of the electronic state
= 1 singlet (default)
= 2,3,... doublet, triplet, and so on.
ICHARG and MULT are used directly for RHF, UHF, ROHF.
For GVB, these are implicit in the $SCF input, while
for MCSCF or CI, these are implicit in $DRT/$CIDRT or
$DET/$CIDET input. You must still give them correctly.
* * * the next three control molecular geometry * * *
COORD = choice for molecular geometry in $DATA.
= UNIQUE only the symmetry unique atoms will be
given, in Cartesian coords (default).
= HINT only the symmetry unique atoms will be
given, in Hilderbrandt style internals.
= CART Cartesian coordinates will be input.
Please read the warning just below!!!
= ZMT GAUSSIAN style internals will be input.
= ZMTMPC MOPAC style internals will be input.
= FRAGONLY means no part of the system is treated
by ab initio means, hence $DATA is not
given. The system is defined by $EFRAG.
Note: the choices CART, ZMT, ZMTMPC require input of all
atoms in the molecule. They also orient the molecule, and
then determine which atoms are unique. The reorientation
is likely to change the order of the atoms from what you
input. When the point group contains a 3fold or higher
rotation axis, the degenerate moments of inertia often
cause problems choosing correct symmetry unique axes, in
which case you must use COORD=UNIQUE rather than Z
matrices.
Warning: The reorientation into principal axes is done
only for atomic coordinates, and is not applied to the axis
dependent data in the following groups: $VEC, $HESS, $GRAD,
$DIPDR, $VIB, nor Cartesian coords of effective fragments
in $EFRAG. COORD=UNIQUE avoids reorientation, and thus is
the safest way to read these.
Note: the choices CART, ZMT, ZMTMPC require the use of a
group named $BASIS to define the basis set. The first two
choices might or might not use $BASIS, as you wish.
UNITS = distance units, any angles must be in degrees.
= ANGS Angstroms (default)
= BOHR Bohr atomic units
NZVAR = 0 Use Cartesian coordinates (default).
= M If COORD=ZMT or ZMTMPC, and $ZMAT is not given:
the internal coordinates will be those defining
the molecule in $DATA. In this case, $DATA may
not contain any dummy atoms. M is usually
3N6, or 3N5 for linear.
= M For other COORD choices, or if $ZMAT is given:
the internal coordinates will be those defined
in $ZMAT. This allows more sophisticated
internal coordinate choices. M is ordinarily
3N6 (3N5), unless $ZMAT has linear bends.
NZVAR refers mainly to the coordinates used by OPTIMIZE
or SADPOINT runs, but may also print the internal's
values for other run types. You can use internals to
define the molecule, but Cartesians during optimizations!
* * * * * * *
ECP = effective core potential control.
= NONE all electron calculation (default).
= READ read the potentials in $ECP group.
= SBKJC use Stevens, Basch, Krauss, Jasien,
Cundari potentials for all heavy
atoms (LiRn are available).
= HW use Hay, Wadt potentials for all the
heavy atoms (NaXe are available).
= MCP use Huzinaga's Model Core Potentials.
Gradients are not available, and see
the $MCP group for how to input these.
* * * * * * *
LOCAL = controls orbital localization.
= NONE Skip localization (default).
= BOYS Do FosterBoys localization.
= RUEDNBRG Do EdmistonRuedenberg localization.
= POP Do PipekMezey population localization.
See the $LOCAL group. Localization
does not work for SCFTYP=GVB or CITYP.
* * * * * * *
ISPHER = Spherical Harmonics option
= 1 Use Cartesian basis functions to construct
symmetryadapted linear combination (SALC)
of basis functions. The SALC space is the
linear variation space used. (default)
= 0 Use spherical harmonic functions to create
SALC functions, which are then expressed
in terms of Cartesian functions. The
contaminants are not dropped, hence this
option has EXACTLY the same variational
space as ISPHER=1. The only benefit to
obtain from this is a population analysis
in terms of pure s,p,d,f,g functions.
= +1 Same as ISPHER=0, but the function space
is truncated to eliminate all contaminant
Cartesian functions [3S(D), 3P(F), 4S(G),
and 3D(G)] before constructing the SALC
functions. The computation corresponds
to the use of a spherical harmonic basis.
QMTTOL = linear dependence threshhold
Any functions in the SALC variational space whose
eigenvalue of the overlap matrix is below this
tolerence is considered to be linearly dependent.
Such functions are dropped from the variational
space. What is dropped is not individual basis
functions, but rather some linear combination(s)
of the entire basis set that represent the linear
dependent part of the function space. The default
is a reasonable value for most purposes, 1.0E6.
When many diffuse functions are used, it is common
to see the program drop some combinations. On
occasion, in multiring molecules, we have raised
QMTTOL to 3.0E6 to obtain SCF convergence, at the
cost of some energy.
MAXIT = Maximum number of SCF iteration cycles. This
pertains only to RHF, UHF, ROHF, or GVB runs.
See also MAXIT in $MCSCF. (default = 30)
* * * interfaces to other programs * * *
MOLPLT = flag that produces an input deck for a molecule
drawing program distributed with GAMESS.
(default is .FALSE.)
PLTORB = flag that produces an input deck for an orbital
plotting program distributed with GAMESS.
(default is .FALSE.)
AIMPAC = flag to create an input deck for Bader's Atoms
In Molecules properties code. (default=.FALSE.)
For information about this program, see the URL
http://www.chemistry.mcmaster.ca/faculty/bader/aim
FRIEND = string to prepare input to other quantum
programs, choose from
= HONDO for HONDO 8.2
= MELDF for MELDF
= GAMESSUK for GAMESS (UK Daresbury version)
= GAUSSIAN for Gaussian 9x
= ALL for all of the above
PLTORB, MOLPLT, and AIMPAC decks are written to file
PUNCH at the end of the job. Thus all of these correspond
to the final geometry encountered during jobs such as
OPTIMIZE, SAPDOINT, IRC...
In contrast, selecting FRIEND turns the job into a
CHECK run only, no matter how you set EXETYP. Thus the
geometry is that encountered in $DATA. The input is
added to the PUNCH file, and may require some (usually
minimal) massaging.
PLTORB and MOLPLT are written even for EXETYP=CHECK.
AIMPAC requires at least RUNTYP=PROP.
* * * computation control switches * * *
For the most part, the default is the only sensible
value, and unless you are sure of what you are doing,
these probably should not be touched.
NPRINT = Print/punch control flag
See also EXETYP for debug info.
(options 7 to 5 are primarily debug)
= 7 Extra printing from Boys localization.
= 6 debug for geometry searches
= 5 minimal output
= 4 print 2econtribution to gradient.
= 3 print 1econtribution to gradient.
= 2 normal printing, no punch file
= 1 extra printing for basis,symmetry,ZMAT
= 2 extra printing for MO guess routines
= 3 print out property and 1e integrals
= 4 print out 2e integrals
= 5 print out SCF data for each cycle.
(Fock and density matrices, current MOs
= 6 same as 7, but wider 132 columns output.
This option isn't perfect.
= 7 normal printing and punching (default)
= 8 more printout than 7. The extra output
is (AO) Mulliken and overlap population
analysis, eigenvalues, Lagrangians, ...
= 9 everything in 8 plus Lowdin population
analysis, final density matrix.
NOSYM = 0 the symmetry specified in $DATA is used
as much as possible in integrals, SCF,
gradients, etc. (this is the default)
= 1 the symmetry specified in the $DATA group
is used to build the molecule, then
symmetry is not used again. Some GVB
or MCSCF runs (those without a totally
symmetric charge density) require you
request no symmetry.
INTTYP selects the integral package(s) used, all of which
produce equally accurate results. This is therefore
used only for debugging purposes.
= BEST use the fastest integral code available for
any particular shell quartet (default):
s,p,L or s,p,d,L rotated axis code first.
ERIC s,p,d,f,g precursor transfer equation
code second, up to 5 units total ang. mom.
Rys quadrature for general s,p,d,f,g,L,
or for uncontracted quartets.
= ROTAXIS means don't use ERIC at all, e.g. rotated
axis codes, or else Rys quadrature.
= ERIC means don't use rotated axis codes, e.g.
ERIC code, or else Rys quadrature.
= RYSQUAD means use Rys quadrature for everything.
GRDTYP = BEST use the Schlegel routines for sp gradient
blocks, and HONDO/Rys polynomial code for
all other gradient integrals. (default)
= HONDO use HONDO/Rys for all integral derivatives.
This option produces very slightly more
accurate gradients but is rather slower.
NORMF = 0 normalize the basis functions (default)
= 1 no normalization
NORMP = 0 input contraction coefficients refer to
normalized Gaussian primitives. (default)
= 1 the opposite.
ITOL = primitive cutoff factor (default=20)
= n products of primitives whose exponential
factor is less than 10**(n) are skipped.
ICUT = n integrals less than 10.0**(n) are not
saved on disk. (default = 9). Direct
SCF will calculate to a cutoff 1.0d10
or 5.0d11 depending on FDIFF=.F. or .T.
* * * restart options * * *
IREST = restart control options
(for OPTIMIZE run restarts, see $STATPT)
Note that this option is unreliable!
= 1 reuse dictionary file from previous run,
useful with GEOM=DAF and/or GUESS=MOSAVED.
Otherwise, this option is the same as 0.
= 0 normal run (default)
= 1 2e restart (1e integrals and MOs saved)
= 2 SCF restart (1,2e integrls and MOs saved)
= 3 1e gradient restart
= 4 2e gradient restart
GEOM = select where to obtain molecular geometry
= INPUT from $DATA input (default for IREST=0)
= DAF read from DICTNRY file (default otherwise)
As noted in the first chapter, binary file restart is
not a well tested option!
==========================================================
==========================================================
$SYSTEM group (optional)
This group provides global control information for
your computer's operation. This is system related input,
and will not seem particularly chemical to you!
TIMLIM = time limit, in minutes. Set to about 95 percent
of the time limit given to the batch job (if you
use a queueing system) so that GAMESS can stop
itself gently. (default=525600.0 minutes)
MWORDS = the maximum replicated memory which your job can
use, on every node. This is given in units of
1,000,000 words (as opposed to 1024*1024 words),
where a word is always a 64 bit quantity. Most
systems allocate this memory at run time, but
some more primitive systems may have an upper
limit chosen at compile time. (default=1)
In case finer control over the memory is needed,
this value can be given in units of words by
using the keyword MEMORY instead of MWORDS.
MEMDDI = the grand total memory needed for the distributed
data interface (DDI) storage, given in units of
1,000,000 words. See Chapter 5 of this manual for
an extended explanation of running with MEMDDI.
note: the memory required on each node for a run using
p processors is therefore MEMDDI/p + MWORDS.
The parallel runs that currently require MEMDDI are:
SCFTYP=RHF MPLEVL=2 energy or gradient
SCFTYP=UHF MPLEVL=2 energy or gradient
SCFTYP=ROHF MPLEVL=2 OSPT=ZAPT energy or gradient
SCFTYP=MCSCF MPLEVL=2 energy
SCFTYP=MCSCF FULLNR=.TRUE.
SCFTYP=any CITYP=GUGA
All other parallel runs should enter MEMDDI=0.
PARALL = a flag to cause the distributed data parallel
MP2 program to execute the parallel algorithm,
even if you are running on only one node.
The main purpose of this is to allow you to
do EXETYP=CHECK runs to learn what the correct
value of MEMDDI needs to be.
KDIAG = diagonalization control switch
= 0 use a vectorized diagonalization routine
if one is available on your machine,
else use EVVRSP. (default)
= 1 use EVVRSP diagonalization. This may
be more accurate than KDIAG=0.
= 2 use GIVEIS diagonalization
(not as fast or reliable as EVVRSP)
= 3 use JACOBI diagonalization
(this is the slowest method)
COREFL = a flag to indicate whether or not GAMESS
should produce a "core" file for debugging
when subroutine ABRT is called to kill
a job. This variable pertains only to
UNIX operating systems. (default=.FALSE.)
BALTYP = Parallel load balance scheme:
LOOP uses static load balancing.
NXTVAL uses dynamic load balancing (DLB).
(default = NXTVAL)
==========================================================
==========================================================
$BASIS group (optional)
This group allows certain standard basis sets to be
easily requested. If this group is omitted, the basis set
must be given in the $DATA group input.
GBASIS requests various Gaussian basis sets.
* * * segemented contractions * * *
GBASIS = MINI  Huzinaga's 3 gaussian minimal basis set.
Available HRn.
= MIDI  Huzinaga's 21 split valence basis set.
Available HRn.
= STO  Pople's STONG minimal basis set.
Available HXe, for NGAUSS=2,3,4,5,6.
= N21  Pople's N21G split valence basis set.
Available HXe, for NGAUSS=3.
Available HAr, for NGAUSS=6.
= N31  Pople's N31G split valence basis set.
Available HNe,PCl for NGAUSS=4.
Available HHe,CF for NGAUSS=5.
Available HZn, for NGAUSS=6.
For GaKr, N31 selects the BC basis.
= N311  Pople's "triple split" N311G basis set.
Available HNe, for NGAUSS=6.
Selecting N311 implies MC for NaAr.
= DZV  "double zeta valence" basis set.
a synonym for DH for H,Li,BeNe,AlCl.
(14s,9p,3d)/[5s,3p,1d] for KCa.
(14s,11p,5d/[6s,4p,1d] for GaKr.
= DH  Dunning/Hay "double zeta" basis set.
(3s)/[2s] for H.
(9s,4p)/[3s,2p] for Li.
(9s,5p)/[3s,2p] for BeNe.
(11s,7p)/[6s,4p] for AlCl.
= TZV  "triple zeta valence" basis set.
(5s)/[3s] for H.
(10s,3p)/[4s,3p] for Li.
(10s,6p)/[5s,3p] for BeNe.
a synonym for MC for NaAr.
(14s,9p)/[8s,4p] for KCa.
(14s,11p,6d)/[10s,8p,3d] for ScZn.
= MC  McLean/Chandler "triple split" basis.
(12s,9p)/[6s,5p] for NaAr.
Selecting MC implies 6311G for HNe.
Note: Polarization functions and/or diffuse functions are
to be added separately to these GBASIS values, which define
only the atom's occupied orbitals, with keywords such as
NDFUNC and DIFFSP. Pople GBASIS keywords require NGAUSS.
* * * systematic basis set families * * *
GBASIS = CCn  Dunningtype Correlation Consistent basis
sets, officially called ccpVnZ.
Use n = D,T,Q,5,6 to indicate the level of
polarization. These provide a hierachy of
basis sets suitable for recovering the
correlation energy.
Available for HHe, LiNe, NaAr, Ca, GaKr
= ACCn  As CCn, but augmented with a set of diffuse
functions, e.g. augccpVnZ.
= CCnC  As CCn, but augmented with tight functions
for recovering core and corevalence
correlation, e.g. ccpCVnZ.
= ACCnC As CCn, but augmented with both tight and
diffuse functions, e.g. augccpCVnZ.
= PCn  Jensen Polarization Consistent basis sets.
n = 0,1,2,3,4 indicates the level of
polarization. (n=0 is unpolarized, n=1 is
DZP, n=2 is TZP, etc.). These provide a
hierachy of basis sets suitable for DFT and
HF calculations.
Available for H, C,N,O,F, Si,P,S,Cl
= APCn  As PCn, but augmented with a set of diffuse
functions.
Notes:
1. The CC5, CC6, and PC4 basis sets (and corresponding
augmented versions) contain hfunctions, and CC6 contains
ifunctions. As GAMESS' integral codes are currently
restricted to gfunctions, these basis sets presently just
omit these functions, and therefore are not the standard
ones.
2. The implementations of the ccpVnZ basis sets for AlAr
include one additional tight dfunction, as this has been
found to improve the results.
3. Note that both the CC and PC basis sets are generally
contracted, which GAMESS can only handle by replicating the
primitive basis functions, leading to a less than optimum
performance in AO integral evaluation.
4. Normally these basis sets are used only as spherical
harmonics, see ISPHER=1 in $CONTRL.
* * * Effective Core Potential (ECP) bases * * *
GBASIS = SBKJC Stevens/Basch/Krauss/Jasien/Cundari
valence basis set, for LiRn. This choice
implies an unscaled 31G basis for HHe.
= HW  Hay/Wadt valence basis.
This is a 21 split, available NaXe,
except for the transition metals.
This implies a 321G basis for HNe.
* * * semiempirical basis sets * * *
GBASIS = MNDO  selects MNDO model hamiltonian
= AM1  selects AM1 model hamiltonian
= PM3  selects PM3 model hamiltonian
Note: The elements for which these exist can be found in
the 'further information' section of this manual. If you
pick one of these, all other data in this group is ignored.
Semiempirical runs actually use valenceonly Slater type
orbitals (STO), not Gaussian GTOs, but the keyword is
GBASIS anyway. NDFUNC, etc. will be ignored for these.
 supplementary functions 
NGAUSS = the number of Gaussians (N). This parameter
pertains only to GBASIS=STO, N21, N31, or N311.
NDFUNC = number of heavy atom polarization functions to
be used. These are usually d functions, except
for MINI/MIDI. The term "heavy" means Na on up
when GBASIS=STO, HW, or N21, and from Li on up
otherwise. The value may not exceed 3. The
variable POLAR selects the actual exponents to
be used, see also SPLIT2 and SPLIT3. (default=0)
NFFUNC = number of heavy atom f type polarization
functions to be used on LiCl. This may only
be input as 0 or 1. (default=0)
NPFUNC = number of light atom, p type polarization
functions to be used on HHe. This may not
exceed 3, see also POLAR. (default=0)
DIFFSP = flag to add diffuse sp (L) shell to heavy atoms.
Heavy means LiF, NaCl, GaBr, InI, TlAt.
The default is .FALSE.
DIFFS = flag to add diffuse s shell to hydrogens.
The default is .FALSE.
Warning: if you use diffuse functions, please read QMTTOL
in the $CONTRL group for numerical concerns.
POLAR = exponent of polarization functions
= POPLE (default for all other cases)
= POPN311 (default for GBASIS=N311, MC)
= DUNNING (default for GBASIS=DH, DZV)
= HUZINAGA (default for GBASIS=MINI, MIDI)
= HONDO7 (default for GBASIS=TZV)
SPLIT2 = an array of splitting factors used when NDFUNC
or NPFUNC is 2. Default=2.0,0.5
SPLIT3 = an array of splitting factors used when NDFUNC
or NPFUNC is 3. Default=4.00,1.00,0.25
EXTFIL = a flag to read basis sets from an external file,
defined by EXTBAS, rather than from a $DATA group.
(default=.false.)
No external file is provided with GAMESS, you must create
your own. The GBASIS keyword must give an 8 or less
character string, obviously not using any internally stored
names. Every atom must be defined in the external file by
a line giving the chemical symbol, and this chosen string.
Following this header line, give the basis in free format
$DATA style, containing only S, P, D, F, G, and L shells,
and terminating each atom by the usual blank line. The
externmal file may have several families of bases in the
same file, identified by different GBASIS strings.
=========================================================
The splitting factors are from the Pople school, and are
probably too far apart. See for example the Binning and
Curtiss paper. For example, the SPLIT2 value will usually
cause an INCREASE over the 1d energy at the HF level for
hydrocarbons.
The actual exponents used for polarization functions, as
well as for diffuse sp or s shells, are described in the
'Further References' section of this manual. This section
also describes the sp part of the basis set chosen by
GBASIS fully, with all references cited.
Note that GAMESS always punches a full $DATA group. Thus,
if $BASIS does not quite cover the basis you want, you can
obtain this full $DATA group from EXETYP=CHECK, and then
change polarization exponents, add Rydbergs, etc.
==========================================================
$DATA group (required)
$DATAS group (if NESC chosen, for small component basis)
$DATAL group (if NESC chosen, for large component basis)
This group describes the global molecular data such as
point group symmetry, nuclear coordinates, and possibly
the basis set. It consists of a series of free format
card images. See $RELWFN for more information on large and
small component basis sets. The input structure of $DATAS
and $DATAL is identical to the COORD=UNIQUE $DATA input.

1 TITLE a single descriptive title card.

2 GROUP, NAXIS
GROUP is the Schoenflies symbol of the symmetry group,
you may choose from
C1, Cs, Ci, Cn, S2n, Cnh, Cnv, Dn, Dnh, Dnd,
T, Th, Td, O, Oh.
NAXIS is the order of the highest rotation axis, and
must be given when the name of the group contains an N.
For example, "Cnv 2" is C2v. "S2n 3" means S6. Use of
NAXIS up to 8 is supported in each axial groups.
For linear molecules, choose either Cnv or Dnh, and enter
NAXIS as 4. Enter atoms as Dnh with NAXIS=2. If the
electronic state of either is degenerate, check the note
about the effect of symmetry in the electronic state
in the SCF section of REFS.DOC.

In order to use GAMESS effectively, you must be able
to recognize the point group name for your molecule. This
presupposes a knowledge of group theory at about the level
of Cotton's "Group Theory", Chapter 3.
Armed with only the name of the group, GAMESS is able
to exploit the molecular symmetry throughout almost all of
the program, and thus save a great deal of computer time.
GAMESS does not require that you know very much else about
group theory, although a deeper knowledge (character
tables, irreducible representations, term symbols, and so
on) is useful when dealing with the more sophisticated
wavefunctions.
Cards 3 and 4 are quite complicated, and are rarely
given. A *SINGLE* blank card may replace both cards 3
and 4, to select the 'master frame', which is defined on
the next page. If you choose to enter a blank line, skip
to one of the 5 input sequences.
Note!
If the point group is C1 (no symmetry), skip over cards
3 and 4 (which means no blank card).

3 X1, Y1, Z1, X2, Y2, Z2
For C1 group, there is no card 3 or 4.
For CI group, give one point, the center of inversion.
For CS group, any two points in the symmetry plane.
For axial groups, any two points on the principal axis.
For tetrahedral groups, any two points on a twofold axis.
For octahedral groups, any two points on a fourfold axis.

4 X3, Y3, Z3, DIRECT
third point, and a directional parameter.
For CS group, one point of the symmetry plane,
noncollinear with points 1 and 2.
For CI group, there is no card 4.
For other groups, a generator sigmav plane (if any) is
the (x,z) plane of the local frame (CNV point groups).
A generator sigmah plane (if any) is the (x,y) plane of
the local frame (CNH and dihedral groups).
A generator C2 axis (if any) is the xaxis of the local
frame (dihedral groups).
The perpendicular to the principal axis passing through
the third point defines a direction called D1. If
DIRECT='PARALLEL', the xaxis of the local frame coincides
with the direction D1. If DIRECT='NORMAL', the xaxis of
the local frame is the common perpendicular to D1 and the
principal axis, passing through the intersection point of
these two lines. Thus D1 coincides in this case with the
negative y axis.

The 'master frame' is just a standard orientation for
the molecule. By default, the 'master frame' assumes that
1. z is the principal rotation axis (if any),
2. x is a perpendicular twofold axis (if any),
3. xz is the sigmav plane (if any), and
4. xy is the sigmah plane (if any).
Use the lowest number rule that applies to your molecule.
Some examples of these rules:
Ammonia (C3v): the unique H lies in the XZ plane (R1,R3).
Ethane (D3d): the unique H lies in the YZ plane (R1,R2).
Methane (Td): the H lies in the XYZ direction (R2). Since
there is more than one 3fold, R1 does not apply.
HP=O (Cs): the mirror plane is the XY plane (R4).
In general, it is a poor idea to try to reorient the
molecule. Certain sections of the program, such as the
orbital symmetry assignment, do not know how to deal with
cases where the 'master frame' has been changed.
Linear molecules (C4v or D4h) must lie along the z axis,
so do not try to reorient linear molecules.
You can use EXETYP=CHECK to quickly find what atoms are
generated, and in what order. This is typically necessary
in order to use the general $ZMAT coordinates.
* * * *
Depending on your choice for COORD in $CONTROL,
if COORD=UNIQUE, follow card sequence U
if COORD=HINT, follow card sequence U
if COORD=CART, follow card sequence C
if COORD=ZMT, follow card sequence G
if COORD=ZMTMPC, follow card sequence M
Card sequence U is the only one which allows you to define
a completely general basis here in $DATA.
Recall that UNIT in $CONTRL determines the distance units.

5U Atom input. Only the symmetry unique atoms are
input, GAMESS will generate the symmetry equivalent atoms
according to the point group selected above.
if COORD=UNIQUE NAME, ZNUC, X, Y, Z
***************
NAME = 10 character atomic name, used only for printout.
Thus you can enter H or Hydrogen, or whatever.
ZNUC = nuclear charge. It is the nuclear charge which
actually defines the atom's identity.
X,Y,Z = Cartesian coordinates.
if COORD=HINT
*************
NAME,ZNUC,CONX,R,ALPHA,BETA,SIGN,POINT1,POINT2,POINT3
NAME = 10 character atomic name (used only for print out).
ZNUC = nuclear charge.
CONX = connection type, choose from
'LC' linear conn. 'CCPA' central conn.
'PCC' planar central conn. with polar atom
'NPCC' nonplanar central conn. 'TCT' terminal conn.
'PTC' planar terminal conn. with torsion
R = connection distance.
ALPHA= first connection angle
BETA = second connection angle
SIGN = connection sign, '+' or ''
POINT1, POINT2, POINT3 =
connection points, a serial number of a previously
input atom, or one of 4 standard points: O,I,J,K
(origin and unit points on axes of master frame).
defaults: POINT1='O', POINT2='I', POINT3='J'
ref R.L. Hilderbrandt, J.Chem.Phys. 51, 1654 (1969).
You cannot understand HINT input without reading this.
Note that if ZNUC is negative, the internally stored
basis for ABS(ZNUC) is placed on this center, but the
calculation uses ZNUC=0 after this. This is useful
for basis set superposition error (BSSE) calculations.

* * * If you gave $BASIS, continue entering cards 5U
until all the unique atoms have been specified.
When you are done, enter a " $END " card.
* * * If you did not, enter cards 6U, 7U, 8U.

6U GBASIS, NGAUSS, (SCALF(i),i=1,4)
GBASIS has exactly the same meaning as in $BASIS. You may
choose from MINI, MIDI, STO, N21, N31, N311, DZV, DH, BC,
TZV, MC, SBKJC, or HW. In addition, you may choose S, P,
D, F, G, or L to enter an explicit basis set. Here, L
means both an s and p shell with a shared exponent.
In addition, GBASIS may be defined as MCP, to indicate that
the current atom is represented by a model core potential.
MCP must be followed by the keyword READ to indicate that
the basis functions are read using the sequence 6U, 7U,
and 8U, as presently there are no built in basis sets.
In addition, MCP implies that the parameters of the model
core potentials together with core basis functions are in
the input stream in a $MCP group.
NGAUSS is the number of Gaussians (N) in the Pople style
basis, or user input general basis. It has meaning only
for GBASIS=STO, N21, N31, or N311, and S,P,D,F,G, or L.
Up to four scale factors may be entered. If omitted,
standard values are used. They are not documented as
every GBASIS treats these differently. Read the source
code if you need to know more. They are seldom given.

* * * If GBASIS is not S,P,D,F,G, or L, either add more
shells by repeating card 6U, or go on to 8U.
* * * If GBASIS=S,P,D,F,G, or L, enter NGAUSS cards 7U.

7U IG, ZETA, C1, C2
IG = a counter, IG takes values 1, 2, ..., NGAUSS.
ZETA = Gaussian exponent of the IG'th primitive.
C1 = Contraction coefficient for S,P,D,F,G shells,
and for the s function of L shells.
C2 = Contraction coefficient for the p in L shells.

* * * For more shells on this atom, go back to card 6U.
* * * If there are no more shells, go on to card 8U.

8U A blank card ends the basis set for this atom.

Continue entering atoms with 5U through 8U until all
are given, then terminate the group with a " $END " card.
 this is the end of card sequence U 
COORD=CART input:

5C Atom input.
Cartesian coordinates for all atoms must be entered. They
may be arbitrarily rotated or translated, but must possess
the actual point group symmetry. GAMESS will reorient the
molecule into the 'master frame', and determine which
atoms are the unique ones. Thus, the final order of the
atoms may be different from what you enter here.
NAME, ZNUC, X, Y, Z
NAME = 10 character atomic name, used only for printout.
Thus you can enter H or Hydrogen, or whatever.
ZNUC = nuclear charge. It is the nuclear charge which
actually defines the atom's identity.
X,Y,Z = Cartesian coordinates.

Continue entering atoms with card 5C until all are
given, and then terminate the group with a " $END " card.
 this is the end of card sequence C 
COORD=ZMT input: (GAUSSIAN style internals)

5G ATOM
Only the name of the first atom is required.
See 8G for a description of this information.

6G ATOM i1 BLENGTH
Only a name and a bond distance is required for atom 2.
See 8G for a description of this information.

7G ATOM i1 BLENGTH i2 ALPHA
Only a name, distance, and angle are required for atom 3.
See 8G for a description of this information.

8G ATOM i1 BLENGTH i2 ALPHA i3 BETA i4
ATOM is the chemical symbol of this atom. It can be
followed by numbers, if desired, for example Si3.
The chemical symbol implies the nuclear charge.
i1 defines the connectivity of the following bond.
BLENGTH is the bond length "this atomatom i1".
i2 defines the connectivity of the following angle.
ALPHA is the angle "this atomatom i1atom i2".
i3 defines the connectivity of the following angle.
BETA is either the dihedral angle "this atomatom i1
atom i2atom i3", or perhaps a second bond
angle "this atomatom i1atom i3".
i4 defines the nature of BETA,
If BETA is a dihedral angle, i4=0 (default).
If BETA is a second bond angle, i4=+/1.
(sign specifies one of two possible directions).

o Repeat 8G for atoms 4, 5, ...
o The use of ghost atoms is possible, by using X or BQ
for the chemical symbol. Ghost atoms preclude the
option of an automatic generation of $ZMAT.
o The connectivity i1, i2, i3 may be given as integers,
1, 2, 3, 4, 5,... or as strings which match one of
the ATOMs. In this case, numbers must be added to the
ATOM strings to ensure uniqueness!
o In 6G to 8G, symbolic strings may be given in
place of numeric values for BLENGTH, ALPHA, and BETA.
The same string may be repeated, which is handy in
enforcing symmetry. If the string is preceeded by a
minus sign, the numeric value which will be used is
the opposite, of course. Any mixture of numeric data
and symbols may be given. If any strings were given
in 6G to 8G, you must provide cards 9G and
10G, otherwise you may terminate the group now with
a " $END " card.

9G A blank line terminates the Zmatrix section.

10G STRING VALUE
STRING is a symbolic string used in the Zmatrix.
VALUE is the numeric value to substitute for that string.

Continue entering 10G until all STRINGs are defined.
Note that any blank card encountered while reading 10G
will be ignored. GAMESS regards all STRINGs as variables
(constraints are sometimes applied in $STATPT). It is not
necessary to place constraints to preserve point group
symmetry, as GAMESS will never lower the symmetry from
that given at 2. When you have given all STRINGs a
VALUE, terminate the group with a " $END " card.
 this is the end of card sequence G 
* * * *
The documentation for sequence G above and sequence M
below presumes you are reasonably familiar with the input
to GAUSSIAN or MOPAC. It is probably too terse to be
understood very well if you are unfamiliar with these. A
good tutorial on both styles of Zmatrix input can be
found in Tim Clark's book "A Handbook of Computational
Chemistry", published by John Wiley & Sons, 1985.
Both Zmatrix input styles must generate a molecule
which possesses the symmetry you requested at 2. If
not, your job will be terminated automatically.
COORD=ZMTMPC input: (MOPAC style internals)

5M ATOM
Only the name of the first atom is required.
See 8M for a description of this information.

6M ATOM BLENGTH
Only a name and a bond distance is required for atom 2.
See 8M for a description of this information.

7M ATOM BLENGTH j1 ALPHA j2
Only a bond distance from atom 2, and an angle with repect
to atom 1 is required for atom 3. If you prefer to hook
atom 3 to atom 1, you must give connectivity as in 8M.
See 8M for a description of this information.

8M ATOM BLENGTH j1 ALPHA j2 BETA j3 i1 i2 i3
ATOM, BLENGTH, ALPHA, BETA, i1, i2 and i3 are as described
at 8G. However, BLENGTH, ALPHA, and BETA must be given
as numerical values only. In addition, BETA is always a
dihedral angle. i1, i2, i3 must be integers only.
The j1, j2 and j3 integers, used in MOPAC to signal
optimization of parameters, must be supplied but are
ignored here. You may give them as 0, for example.

Continue entering atoms 3, 4, 5, ... with 8M cards until
all are given, and then terminate the group by giving a
" $END " card.
 this is the end of card sequence M 
==========================================================
This is the end of $DATA!
If you have any doubt about what molecule and basis set
you are defining, or what order the atoms will be
generated in, simply execute an EXETYP=CHECK job to find
out!
==========================================================
$ZMAT group (required if NZVAR is nonzero in $CONTRL)
This group lets you define the internal coordinates in
which the gradient geometry search is carried out. These
need not be the same as the internal coordinates used in
$DATA. The coordinates may be simple Zmatrix types,
delocalized coordinates, or natural internal coordinates.
You must input a total of M=3N6 internal coordinates
(M=3N5 for linear molecules). NZVAR in $CONTRL can be
less than M IF AND ONLY IF you are using linear bends. It
is also possible to input more than M coordinates if they
are used to form exactly M linear combinations for new
internals. These may be symmetry coordinates or natural
internal coordinates. If NZVAR > M, you must input IJS and
SIJ below to form M new coordinates. See DECOMP in $FORCE
for the only circumstance in which you may enter a larger
NZVAR without giving SIJ and IJS.
**** IZMAT defines simple internal coordinates ****
IZMAT is an array of integers defining each coordinate.
The general form for each internal coordinate is
code number,I,J,K,L,M,N
IZMAT =1 followed by two atom numbers. (IJ bond length)
=2 followed by three numbers. (IJK bond angle)
=3 followed by four numbers. (dihedral angle)
Torsion angle between planes IJK and JKL.
=4 followed by four atom numbers. (atomplane)
Outofplane angle from bond IJ to plane JKL.
=5 followed by three numbers. (IJK linear bend)
Counts as 2 coordinates for the degenerate bend,
normally J is the center atom. See $LIBE.
=6 followed by five atom numbers. (dihedral angle)
Dihedral angle between planes IJK and KLM.
=7 followed by six atom numbers. (ghost torsion)
Let A be the midpoint between atoms I and J, and
B be the midpoint between atoms M and N. This
coordinate is the dihedral angle AKLB. The
atoms I,J and/or M,N may be the same atom number.
(If I=J AND M=N, this is a conventional torsion).
Examples: N2H4, or, with one common pair, H2POH.
Example  a nonlinear triatomic, atom 2 in the middle:
$ZMAT IZMAT(1)=1,1,2, 2,1,2,3, 1,2,3 $END
This sets up two bonds and the angle between them.
The blanks between each coordinate definition are
not necessary, but improve readability mightily.
**** the next define delocalized coordinates ****
DLC is a flag to request delocalized coordinates.
(default is .FALSE.)
AUTO is a flag to generate all redundant coordinates,
automatically. The DLC space will consist of all
nonredundant combinations of these which can be
found. The list of redundant coordinates will
consist of bonds, angles, and torsions only.
(default is .FALSE.)
NONVDW is an array of atom pairs which are to be joined
by a bond, but might be skipped by the routine
that automatically includes all distances shorter
than the sum of van der Waals radii. Any angles
and torsions associated with the new bond(s) are
also automatically included.
The format for IXZMAT, IRZMAT, IFZMAT is that of IZMAT:
IXZMAT is an extra array of simple internal coordinates
which you want to have added to the list generated
by AUTO. Unlike NONVDW, IXZMAT will add only the
coordinate(s) you specify.
IRZMAT is an array of simple internal coordinates which
you would like to remove from the AUTO list of
redundant coordinates. It is sometimes necessary
to remove a torsion if other torsions around a bond
are being frozen, to obtain a nonsingular G matrix.
IFZMAT is an array of simple internal coordinates which
you would like to freeze. See also FVALUE below.
Note that IFZMAT/FVALUE work only with DLC, see the
IFREEZ option in $STATPT to freeze coordinates if
you wish to freeze simple or natural coordinates.
FVALUE is an array of values to which the internal
coordinates should be constrained. It is not
necessary to input $DATA such that the initial
values match these desired final values, but it is
helpful if the initial values are not too far away.
**** SIJ,IJS define natural internal coordinates ****
SIJ is a transformation matrix of dimension NZVAR x M,
used to transform the NZVAR internal coordinates in
IZMAT into M new internal coordinates. SIJ is a
sparse matrix, so only the nonzero elements are
given, by using the IJS array described below.
The columns of SIJ will be normalized by GAMESS.
(Default: SIJ = I, unit matrix)
IJS is an array of pairs of indices, giving the row and
column index of the entries in SIJ.
example  if the above triatomic is water, using
IJS(1) = 1,1, 3,1, 1,2, 3,2, 2,3
SIJ(1) = 1.0, 1.0, 1.0,1.0, 1.0
gives the matrix S= 1.0 1.0 0.0
0.0 0.0 1.0
1.0 1.0 0.0
which defines the symmetric stretch, asymmetric stretch,
and bend of water.
references for natural internal coordinates:
P.Pulay, G.Fogarasi, F.Pang, J.E.Boggs
J.Am.Chem.Soc. 101, 25502560(1979)
G.Fogarasi, X.Zhou, P.W.Taylor, P.Pulay
J.Am.Chem.Soc. 114, 81918201(1992)
reference for delocalized coordinates:
J.Baker, A. Kessi, B.Delley
J.Chem.Phys. 105, 192212(1996)
==========================================================
==========================================================
$LIBE group (required if linear bends are used in $ZMAT)
A degenerate linear bend occurs in two orthogonal planes,
which are specified with the help of a point A. The first
bend occurs in a plane containing the atoms I,J,K and the
user input point A. The second bend is in the plane
perpendicular to this, and containing I,J,K. One such
point must be given for each pair of bends used.
APTS(1)= x1,y1,z1,x2,y2,z2,... for linear bends 1,2,...
Note that each linear bend serves as two coordinates, so
that if you enter 2 linear bends (HCCH, for example), the
correct value of NZVAR is M2, where M=3N6 or 3N5, as
appropriate.
==========================================================
==========================================================
$SCF group relevant if SCFTYP = RHF, UHF, or ROHF,
required if SCFTYP = GVB)
This group of parameters provides additional control
over the RHF, UHF, ROHF, or GVB SCF steps. It must be
given for GVB open shell or perfect pairing wavefunctions.
DIRSCF = a flag to activate a direct SCF calculation,
which is implemented for all the HartreeFock
type wavefunctions: RHF, ROHF, UHF, and GVB.
This keyword also selects direct MP2 computation.
The default of .FALSE. stores integrals on disk
storage for a conventional SCF calculation.
FDIFF = a flag to compute only the change in the Fock
matrices since the previous iteration, rather
than recomputing all two electron contributions.
This saves much CPU time in the later iterations.
This pertains only to direct SCF, and has a
default of .TRUE. This option is implemented
only for the RHF, ROHF, UHF cases.
Cases with many diffuse functions in the basis
set sometimes oscillate at the end, rather than
converging. Turning this parameter off will
normally give convergence.
 The next flags affect convergence rates.
NOCONV = .TRUE. means neither SOSCF nor DIIS will be used.
The default is .FALSE., making the choice of the
primary converger as follows:
for RHF, GVB, or Abelian group ROHF: SOSCF.
for any DFT, UHF, or nonAbelian ROHF: DIIS.
DIIS = selects Pulay's DIIS interpolation.
SOSCF = selects second order SCF orbital optimization.
Once either DIIS or SOSCF are initiated, the following
less important accelerators are put in abeyance:
EXTRAP = selects Pople extrapolation of the Fock matrix.
DAMP = selects Davidson damping of the Fock matrix.
SHIFT = selects level shifting of the Fock matrix.
RSTRCT = selects restriction of orbital interchanges.
DEM = selects direct energy minimization, which is
implemented only for RHF. (default=.FALSE.)
defaults for EXTRAP DAMP SHIFT RSTRCT DIIS SOSCF
ab initio: T F F F F/T T/F
semiempirical: T F F F F F
The above parameters are implemented for all SCF
wavefunction types, except that DIIS will work for GVB
only for those cases with NPAIR=0 or NPAIR=1.
 These parameters fine tune the various convergers.
CONV = SCF density convergence criteria.
Convergence is reached when the density change
between two consecutive SCF cycles is less than
this in absolute value. One more cycle will be
executed after reaching convergence. Less
accuracy in CONV gives questionable gradients.
The default is 1.0d05, except runs involving
CI or MP2 gradients or CC energies use 1.0d06.
SOGTOL = second order gradient tolerance. SOSCF will be
initiated when the orbital gradient falls below
this threshold. (default=0.25 au)
ETHRSH = energy error threshold for initiating DIIS. The
DIIS error is the largest element of e=FDSSDF.
Increasing ETHRSH forces DIIS on sooner.
(default = 0.5 Hartree)
MAXDII = Maximum size of the DIIS linear equations, so
that at most MAXDII1 Fock matrices are used
in the interpolation. (default=10)
SWDIIS = density matrix convergence at which to switch
from DIIS to SOSCF. A value of zero means to
keep using DIIS at all geometries, which is the
default. However, it may be useful to have
DIIS work only at the first geometry, in the
initial iterations, for example transition
metal ECP runs which has a less good Huckel
guess, and then use SOSCF for the final SCF
iterations at the first geometry, and ever
afterwards. A suggested usage might be
DIIS=.TRUE. ETHRSH=2.0 SWDIIS=0.005.
This option is not programmed for GVB.
DEMCUT = Direct energy minimization will not be done
once the density matrix change falls below
this threshold. (Default=0.5)
DMPCUT = Damping factor lower bound cutoff. The damping
damping factor will not be allowed to drop
below this value. (default=0.0)
note: The damping factor need not be zero to achieve
valid convergence (see Hsu, Davidson, and
Pitzer, J.Chem.Phys., 65, 609 (1976), see
especially the section on convergence control),
but it should not be astronomical either.
* * * * * * * * * * * * * * * * * * * * *
For more info on the convergence methods,
see the 'Further Information' section.
* * * * * * * * * * * * * * * * * * * * *
 miscellaneous options 
NPUNCH = SCF punch option
= 0 do not punch out the final orbitals
= 1 punch out the occupied orbitals
= 2 punch out occupied and virtual orbitals
The default is NPUNCH = 2.
UHFNOS = flag controlling generation of the natural
orbitals of a UHF function. (default=.FALSE.)
MVOQ = 0 Skip MVO generation (default)
= n Form modified virtual orbitals, using a cation
with n electrons removed. Implemented for
RHF, ROHF, and GVB. If necessary to reach a
closed shell cation, the program might remove
n+1 electrons. Typically, n will be about 6.
= 1 The cation used will have each valence orbital
half filled, to produce MVOs with valencelike
character in all regions of the molecule.
Implemented for RHF and ROHF only.
ACAVO = Flag to request Approximate CorrelationAdapted
Virtual Orbitals. Implemented for RHF, ROHF,
and GVB. The default is .FALSE.
PACAVO = Parameters used to define the ACAVO generating
operator, which is defined as
a*T + b*Vne + c*Jcore + d*Jval + e*Kcore + f*Kval
The default corresponds to Whitten orbitals,
J.L.Whitten, J.Chem.Phys. 56, 458546(1972)
which maximize the exchange interaction with
the valence orbitals, PACAVO(1)=0,0,0,0,0,1.0.
A set of parameters which may produce a lower
CISD energy, is 0.02,0.02,0.0,0.10,0.0,1.0.
Of course, the normal canonical virtuals come
from PACAVO(1)=1.0,1.0,2.0,2.0,1.0,1.0.
 options for virial scaling 
VTSCAL = A flag to request that the virial theorem be
satisfied. An analysis of the total energy
as an exact sum of orbital kinetic energies
is printed. The default is .FALSE.
This option is implemented for RHF, UHF, and ROHF,
for RUNTYP=ENERGY, OPTIMIZE, or SADPOINT. Related
input is as follows:
SCALF = initial exponent scale factor when VTSCAL is
in use, useful when restarting. The default
is 1.0.
MAXVT = maximum number of iterations (at a single
geometry) to satisfy the energy virial theorem.
The default is 20.
VTCONV = convergence criterion for the VT, which is
satisfied when 2 + + R x dE/dR is less
than VTCONV. The default is 1.0D6 Hartree.
For more information on this option, which is most
economically employed during a geometry search, see
M.Lehd and F.Jensen, J.Comput.Chem. 12, 10891096(1991).
The next parameters define the GVB wavefunction. Note
that ALPHA and BETA also have meaning for ROHF. See also
MULT in the $CONTRL group. The GVB wavefunction assumes
orbitals are in the order core, open, pairs.
NCO = The number of closed shell orbitals. The
default almost certainly should be changed!
(default=0).
NSETO = The number of sets of open shells in the
function. Maximum of 10. (default=0)
NO = An array giving the degeneracy of each open
shell set. Give NSETO values.
(default=0,0,0,...).
NPAIR = The number of geminal pairs in the GVB
function. Maximum of 12. The default
corresponds to open shell SCF (default=0).
CICOEF = An array of ordered pairs of CI coefficients
for the GVB pairs. For example, a two pair
case for water, say, might be
CICOEF(1)=0.95,0.05,0.95,0.05. If not
normalized, as in the default, they will be.
This parameter is useful in restarting a GVB
run, with the current CI coefficients.
(default = 0.90,0.20,0.90,0.20,...)
COUPLE = A switch controlling the input of F, ALPHA,
and BETA. The default is to ignore F, ALPHA,
and BETA unless you set this .TRUE., to read
them in. Note that ALPHA and BETA can be
given for ROHF canonicalization, as well
as GVB. (Default=.FALSE.)
F = An vector of fractional occupations.
ALPHA = An array of A coupling coefficients given in
lower triangular order.
BETA = An array of B coupling coefficients given in
lower triangular order.
Note: The default for F, ALPHA, and BETA depends on
the state chosen. Defaults for the most commonly occuring
cases are internally stored.
* * * * * * * * * * * * * * * * * * *
For more discussion of GVB/ROHF input
see the 'further information' section
* * * * * * * * * * * * * * * * * * *
==========================================================
==========================================================
$SCFMI group (optional, relevant if SCFTYP=RHF)
The Self Consistent Field for Molecular Interactions
(SCFMI) method is a modification of the usual Roothaan
equations that avoids basis set superposition error (BSSE)
in intermolecular interaction calculations, by expanding
each monomer's orbitals using only its own basis set.
Thus, the resulting orbitals are not orthogonal. The
presence of a $SCFMI group in the input triggers the use
of this option.
The implementation is limited to ten monomers, treated
at the RHF level. The energy, gradient, and therefore
seminumerical hessian are available. The SCF step may be
run in direct SCF mode, and parallel calculation is also
enabled. The calculation must use Cartesian Gaussian AOs
only, not spherical harmonics. The SCFMI driver differs
from normal RHF calculations, so not all converger methods
are available. Finally, this option is not compatible with
electron correlation treatments (DFT, MP2, CI, or CC).
The first 3 parameters must be given. All atoms of a
fragment must appear consecutively in $DATA.
NFRAGS = number of distinct fragments present. Both
the supermolecule and its constituent monomers
must be well described as closed shells by RHF
wavefunctions.
NF = an array containing the number of doubly
occupied
MOs for each fragment.
MF = an array containing the number of atomic basis
functions located on each fragment.
ITER = maximum number of SCFMI cycles, overriding
the usual MAXIT value. (default is 50).
DTOL = SCFMI density convergence criteria.
(default is 1.0d10)
ALPHA = possible level shift parameter.
(default is 0.0, meaning shifting is not used)
DIISON = a flag to active the DIIS convergence.
(default is .TRUE.)
MXDIIS = the maximum number of previous effective Fock
and
overlap matrices to be used in DIIS
(default=10)
DIISTL = the density change value at which DIIS starts.
(default=0.01)
A Huckel guess is localized by the Boys procedure onto each
fragment to provide starting orbitals for each:
ITLOC = maximum number of iteration in the localization
step (Default is 50)
CNVLOC = convergence parameter for the localization.
(default is .01).
IOPT = prints additional debug information.
= 0 standard outout (default)
= 1 print for each SCFMI cycle MOs, overlap
between the MOs, CPU times.
= 2 print some extra informations in secular
systems solution.
==========================================================
"Modification of Roothan Equations to exclude BSSE
from Molecular Interaction calculations"
E. Gianinetti, M. Raimondi, E. Tornaghi
Int. J. Quantum Chem. 60, 157166 (1996)
"Implementation of Gradient optimization algorithms
and Force Constant computations in BSSEfree direct
and conventional SCF approaches"
A. Famulari, E. Gianinetti, M. Raimondi, M. Sironi
Int. J. Quantum Chem. 69, 151158 (1997)
==========================================================
$DFT group (relevant if SCFTYP=RHF,UHF,ROHF)
Note that if DFTTYP=NONE, an ab initio calculation
will be performed, rather than density functional theory.
This group permits the use of various one electron
(usually empirical) operators instead of the true many
electron Hamiltonian. Two programs are provided, METHOD=
GRID or GRIDFREE. The programs have different functionals
available, and so the keyword DFTTYP and other associated
inputs are documented separately below. Every functional
that has the same name in both lists is the identical
functional, but each METHOD has a few functionals that are
missing in the other.
The grid free implementation is based on the use of
the resolution of the identity to simplify integrals so
that they may be analytically evaluated, without using
grid quadratures. The grid free DFT computations in their
present form have various numerical errors, primarily in
the gradient vectors. Please do not use the gridfree DFT
program without reading the discussion in the 'Further
References' section regarding the gradient accuracy.
The grid based DFT uses a typical grid quadrature to
compute integrals over the rather complicated functionals.
Achieving a selfconsistent field with DFT is rather
more difficult than for normal HF, so DIIS is the default
converger. The use of GUESS=MOREAD to input HF orbitals is
very helpful in facilitating DFT convergence, and at the
least, saves considerable time in doing DFT iterations.
Both DFT programs will run in parallel.
DFTTYP = NONE means no DFT is performed (default)
METHOD = selects grid based DFT or grid free DFT.
= GRID Grid based DFT (default)
= GRIDFREE Grid free DFT
 options for METHOD=GRID 
DFTTYP = specifies exchange and correlation functionals.
pure exchange functionals (no correlation):
= SLATER Slater exchange
= BECKE Becke 1988 exchange
= GILL Gill 1996 exchange
= PBE PerdewBurkeErnzerhof (PBE) exchange
Note that the PBE correlation functional
is not implemented.
pure correlation functionals (HF exchange):
= VWN VoskoWilkNusair correlation, using
their electron gas formula 5 (VWN5)
= LYP LeeYangParr correlation
= OP Oneparameter Progressive correlation
combination functionals:
= SVWN SLATER exchange + VWN5 correlation
Called LDA/LSDA by physicists for
RHF/UHF.
= SLYP SLATER exchange + LYP correlation
= SOP SLATER exchange + OP correlation
= BVWN BECKE exchange + VWN5 correlation
= BLYP BECKE exchange + LYP correlation
= BOP BECKE exchange + OP correlation
= GVWN GILL exchange + VWN5 correlation
= GLYP GILL exchange + LYP correlation
= GOP GILL exchange + OP correlation
= PBEVWN PBE exchange + VWN5 correlation
= PBELYP PBE exchange + LYP correlation
= PBEOP PBE exchange + OP correlation
hybrid functionals:
= BHHLYP HF and BECKE exchange + LYP correlation
= B3LYP this is a hybrid method combining five
functionals, namely Becke + Slater + HF
exchange and LYP + VWN5 correlation.
An extensive bibliography for these functionals can be
found in the 'Further References' section of this manual.
NRAD = number of radial grids in EulerMaclaurin
quadrature. (default=96)
NTHE = number of angle theta grids in GaussLegendre
quadrature. (default=12)
NPHI = number of angle phi grids in GaussLegendre
quadrature. NPHI should be double NTHE so that
points are spherically distributed. (default=24)
NRAD*NTHE*NPHI grid points will be constructed around each
atom. Time is linear in the number of grid points, so be
careful. Energies can be compared only when the identical
grid density has been used, analogous to needing to compare
with the identical basis set expansions. A very accurate
"army grade" grid capable of producing an integration error
less than a microHartree/atom is NRAD=96 NTHE=36 NPHI=72.
The default grid has an error probably no worse than about
20 microHartree/atom, depending on the type of atom.
NRAD0, NTHE0, NPHI0 define a smaller grid used during the
SCF iterations before some initial convergence is reached.
After that, the full grid defined by NRAD, NTHE, NPHI will
be used. This can save considerable CPU time in the early
SCF iterations.
SWITCH = when the change in the density matrix between
iterations falls below this threshhold, switch
to use of the desired full grid (default=3.0E4)
NRAD0 = same as NRAD, but defines initial (smaller) grid.
NTHE0 = same as NTHE, but defines initial (smaller) grid.
NPHI0 = same as NPHI, but defines initial (smaller) grid.
Default values for the initial grid depend upon NRAD, NTHE,
and NPHI. For the default full grid settings, the initial
grid is NRAD0=24, NTHE0=8, NPHI0=16, for other values the
formula is NRAD0 the larger of NRAD/4 or 24, for NTHE0 the
larger of NTHE/3 or 8, and for NPHI0 the larger of NPHI/3
or 16. In case of slow convergence of the SCF or if using
the "army grade grid", NRAD0=48 NTHE0=12 NPHI0=24 and
SWITCH=1.0E4 may be better. Numerical hessian runs set
the coarse grid to the same size as the full grid, by
default.
SWOFF = turn off DFT, to perform pure SCF iterations,
until the density matrix convergence falls below
this threshold. This option is independent of
SWITCH and can be used with or without it. It is
reasonable to pick SWOFF > SWITCH > CONV in $SCF.
SWOFF pertains only to the first geometry that the
run computes, and is automatically disabled if you
choose GUESS=MOREAD to provide initial orbitals.
The default is 5.0d3.
THRESH = threshold for ignoring small contributions to the
Fock matrix. The default is designed to produce
no significant energy loss, even when the grid is
as good as "army grade". If for some reason you
want to turn all threshhold tests off, of course
requiring more CPU, enter 1.0e15.
default: 1.0e4/Natoms/NRAD/NTHE/NPHI
GTHRE = threshold applied to gradients, similar to THRESH.
< 1 assign this value to all thresholds
= 1 use the default thresholds (default).
> 1 divide default thresholds by this value.
For example if you wish to increase accuracy due
to
threshold cutoffs, set GTHRE=10. The default
introduces an of roughly 1e7 (a.u./bohr) in the
gradient.
 options for METHOD=GRIDFREE 
DFTTYP = NONE means ab initio computation (default)
exchange functionals:
= XALPHA XAlpha exchange (alpha=0.7)
= SLATER Slater exchange (alpha=2/3)
= BECKE Becke's 1988 exchange
= DEPRISTO Depristo/Kress exchange
= CAMA Handy et al's mods to Becke exchange
= HALF 5050 mix of Becke and HF exchange
correlation functionals:
= VWN Vosko/Wilke/Nusair correlation, formula 5
= PWLOC Perdew/Wang local correlation
= LYP Lee/Yang/Parr correlation
exchange/correlation functionals:
= BVWN Becke exchange + VWN5 correlation
= BLYP Becke exchange + LYP correlation
= BPWLOC Becke exchange + Perdew/Wang correlation
= B3LYP hybrid HF/Becke/LYP using VWN formula 5
= CAMB CAMA exchange + Cambridge correlation
= XVWN Xalpha exchange + VWN5 correlation
= XPWLOC Xalpha exchange + Perdew/Wang correlation
= SVWN Slater exchange + VWN5 correlation
= SPWLOC Slater exchange + PWLOC correlation
= WIGNER Wigner exchange + correlation
= WS Wigner scaled exchange + correlation
= WIGEXP Wigner exponential exchange + correlation
AUXFUN = AUX0 uses no auxiliary basis set for resolution
of the identity, limiting accuracy.
= AUX3 uses the 3rd generation of RI basis sets,
These are available for the elements H to
Ar, but have been carefully considered for
HNe only. (DEFAULT)
THREE = a flag to use a resolution of the identity to
turn four center overlap integrals into three
center integrals. This can be used only if
no auxiliary basis is employed. (default=.FALSE.)
==========================================================
==========================================================
$MP2 group (relevant to SCFTYP=RHF,UHF,ROHF if MPLEVL=2)
Controls 2nd order MollerPlesset perturbation runs,
if requested by MPLEVL in $CONTRL. MP2 is implemented for
RHF, high spin ROHF, or UHF wavefunctions, but see also
$MRMP for MCSCF. Analytic gradients and the first order
correction to the wavefunction (i.e. properties) are
available for RHF, ROHF (if OSPT=ZAPT), and UHF. The $MP2
group is not usually given. See also the DIRSCF keyword in
$SCF to select direct MP2.
Special serial codes exist for RHF or UHF MP2 energy
or gradient, or the ROHF MP2 energy. Parallel codes using
distributed memory are available for RHF, ROHF, or UHF MP2
gradients. In fact, the only way that ROHF MP2 gradients
can be computed on one node is with the parallel code,
using MEMDDI!
NACORE = n Omits the first n occupied orbitals from the
calculation. The default for n is the number
of chemical core orbitals.
NBCORE = Same as NACORE, for the beta orbitals of UHF.
It is almost always the same value as NACORE.
MP2PRP= a flag to turn on property computation for jobs
jobs with RUNTYP=ENERGY. This is appreciably
more expensive than just evaluating the second
order energy correction alone, so the default
is to skip properties. Properties are always
computed during gradient runs, when they are
an almost free byproduct. (default=.FALSE.)
OSPT= selects open shell spinrestricted perturbation.
This parameter applies only when SCFTYP=ROHF.
Please see the 'further information' section for
more information about this choice.
= ZAPT picks Zaveraged perturbation theory. (default)
= RMP picks RMP (aka ROHFMBPT) perturbation theory.
LMOMP2= a flag to analyze the closed shell MP2 energy
in terms of localized orbitals. Any type of
localized orbital may be used. This option
is implemented only for RHF, and its selection
forces use of the METHOD=3 transformation, in
serial runs only. The default is .FALSE.
CUTOFF= transformed integral retention threshold, the
default is 1.0d9 (1.0d12 in FMO runs).
CPHFBS = BASISMO solves the response equations during
gradient computations in the MO basis. This
is programmed only for RHF references without
frozen core orbitals, when it is the default.
= BASISAO solves the response equations using
AO integrals, for frozen core MP2 with a RHF
reference, or for ROHF or UHF based MP2.
The next 3 input variables apply to any serial MP2 run, or
to parallel ROHF+MP2 runs using OSPT=RMP.
NWORD = controls memory usage. The default uses all
available memory. (default=0)
METHOD= n selects transformation method, 2 being the
segmented transformation, and 3 being a more
conventional two phase bin sort implementation.
3 requires more disk, but less memory. The
default is to attempt method 2 first, and
method 3 second.
AOINTS= defines AO integral storage during conventional
integral transformations, during parallel runs.
DUP stores duplicated AO lists on each node, and
is the default for parallel computers with slow
interprocessor communication, e.g. ethernet.
DIST distributes the AO integral file across all
nodes, and is the default for parallel
computers with high speed communications.
==========================================================
==========================================================
$CIS group required when CITYP=CIS
The CIS method (singly excited CI) is the simplest way
to treat excited states. By Brillouin's Theorem, a single
determinant reference such as RHF will have zero matrix
elements with singly substituted determinants. The ground
state reference therefore has no mixing with the excited
states treated with singles only. Reading the references
given in Section 4 of this manual will show the CIS method
can be thought of as a noncorrelated method, rigorously so
for the ground state, and effectively so for the various
excited states. Some issues making CIS rather less than a
black box method are:
a) any states characterized by important doubles are
simply missing from the calculation.
b) excited states commonly possess Rydberg (diffuse)
character, so the AO basis used must allow this.
c) excited states often have different point group
symmetry than the ground state, so the starting
geometries for these states must reflect their
actual symmetry.
d) excited state surfaces frequently cross, and thus
root flipping may very well occur.
The implementation allows the use of only RHF references,
but can pick up both singlet and triplet excited states.
Nuclear gradients are available, as are properties. The
CIS run automatically includes computation of the dipole
moments of all states, and all pairwise transition dipoles
and oscillator strengths.
NACORE = n Omits the first n occupied orbitals from the
calculation. The default for n is the number
of chemical core orbitals.
NSTATE = Number of states to be found (excluding the
ground state).
ISTATE = State for which properties and/or gradient will
be calculated. Only one state can be chosen.
HAMTYP = Type of CI Hamiltonian to use.
= SAPS spinadapted antisymmetrized product of
the desired MULT will be used (default)
= DETS determinant based, so both singlets and
triplets will be obtained.
MULT = Multiplicity (1 or 3) of the singly excited
SAPS (the reference is necessarily single RHF).
Only relevant for SAPS based run.
DIAGZN = Hamiltonian diagonalization method.
= DAVID use Davidson diagonalization. (default)
= FULL construct the full matrix in memory and
diagonalize, thus determining all states
(not recommended except for small cases).
DGAPRX = Flag to control whether approximate diagonal
elements of the CIS Hamiltonian (based only on
the orbital energies) are used in the Davidson
algorithm. Note, this only affects the rate of
convergence, not the resulting final energies.
If set .FALSE., the exact diagonal elements are
determined and used. Default=.TRUE.
NGSVEC = Dimension of the Hamiltonian submatrix that is
diagonalized to form the initial CI vectors.
The default is the greater of NSTATE*2 and 10.
MXVEC = Maximum number of expansion basis vectors in the
iterative subspace during Davidson iterations,
before the expansion basis is truncated. The
default is the larger of 8*NSTATE and NGSVEC.
NDAVIT = Maximum number of Davidson iterations.
Default=50.
DAVCVG = Convergence criterion for Davidson eigenvectors.
Eigenvector accuracy is proportional to DAVCVG,
while the energy accuracy is proportional to its
square. The default is 1.0E05.
CISPRP = Flag to request the determination of CIS level
properties, using the relaxed density. Relevant
to RUNTYP=ENERGY jobs, although the default is
.FALSE. because additional CPHF calculation will
be required. Properties are a normal by
product of runs involving the CIS gradient.
CHFSLV = Chooses type of CPHF solver to use.
= CONJG selects an ordinary preconditioned
conjugate gradient solver. (default)
= DIIS selects a diislike iterative solver.
RDCISV = Flag to read CIS vectors from a $CISVEC group
in the input file. Default is .FALSE.
MNMEDG = Flag to force the use of the minimal amount of
memory in construction of the CIS Hamiltonian
diagonal elements. This is only relevant when
DGAPRX=.FALSE., and is meant for debug purposes.
The default is .FALSE.
MNMEOP = Flag to force the use of the minimal amount of
memory during the Davidson iterations. This is
for debug purposes. The default is .FALSE.
==========================================================
$CISVEC group required if RDCISV in $CIS is chosen
This is formatted data generated by a previous CIS run, to
be read back in as starting vectors. Sometimes molecular
orbital phase changes make these CI vectors problematic.
==========================================================
==========================================================
$CCINP group (optional, relevant for any CCTYP)
This group controls a coupledcluster calculation of
any type specified by CCTYP in $CONTRL. If omitted, all
valence electrons will be correlated. The excited state
runs EOMCCSD or CREOM also read this group to define the
orbital spaces, and to control the hardwired ground state
CCSD step that preceeds computation of excitations.
See the "Further Information" section of this manual
for more details.
NCORE = gives the number of frozen core orbitals to be
omitted from the CC calculation. The default
is the number of chemical core orbitals.
NFZV = the number of frozen virtual orbitals to be
omitted from the calculation. The default is 0.
MAXCC = defines the maximum number of CCSD (or LCCD, CCD)
iterations. The default is 30.
ICONV = defines the convergence criterion for the cluster
amplitudes. CC iterations are converged when the
maximum change in amplitudes is less than
10**(ICONV). The default is 7, but it tightened
to 8 for FMOCC.
CCPRP = a flag to select computation of the CCSD level
ground state density matrix (see also CCPRPE in
$EOMINP for EOMCCSD level excited states). The
computation takes significant extra time, to
obtain left eigenstates, so the default is .FALSE.
Notes: CCSD is the only level at which properties can be
obtained. Therefore this option can only be chosen for
CCTYP=CCSD, EOMCCSD, or CREOM. The run will change CCTYP
to EOMCCSD if you choose CCSD, and will therefore read the
$EOMINP group's keywords. However, if you don't select
NSTATE in $EOMINP, your original CCTYP=CCSD will not
include anything except the ground state in the EOMCCSD.
Note that the convergence criterion for left eigenstates
will be CVGEOM in $EOMINP, which is set to obtain
excitation energies, and may need tightening. Use of
CCTYP=CREOM will do triples corrections, after doing the
SD level properties.
NWORD = a limit on memory to be used in the CC steps.
The default is 0, meaning all memory available
will be used.
IREST = defines the restart option. If the value of IREST
is greater or equal 3, program will restart from
the earlier CC run. This requires saving the disk
file CCREST from the previous CC run. Values of
IREST between 0 and 3 should not be used. In
general, the value of IREST is used by the program
to set the iteration counter in the restarted run.
The default is 0, meaning no restart is attempted.
MXDIIS = defines the number of cluster amplitude vectors
from previous iterations to be included in the
DIIS extrapolation during the CCSD (or LCCD, CCD)
iterative process. The default value of MXDIIS is
5 for all but small problems. The DIIS solver can
be disengaged by entering MXDIIS = 0. It is not
necessary to change the default value of MXDIIS,
unless the CC equations do not converge in spite
of increasing the value of MAXCC.
AMPTSH = defines a threshold for eliminating small cluster
amplitudes from the CC calculations. Amplitudes
with absolute values smaller than AMPTSH are set
to zero. The default is to retain all small
amplitudes, meaning fully accurate CC iterations.
Default = 0.0.
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$EOMINP group (optional, for CCTYP=EOMCCSD or CREOM)
This group controls the calculation of excited states
by the equation of motion coupled cluster with single and
double excitations, with optional triples corrections.
The input group permits selection of how many states are
computed (machine time is linear in the number of states).
Since the default is only one excited state in the totally
symmetric representation, it is usually necessary to give
this group. The input also allows selection of various
computational procedures.
An excited state coupled cluster run consists of an
RHF calculation, followed by a ground state CCSD (see the
$CCINP group to control the ground state calculation, and
the orbital range correlated), followed by an EOMCCSD
calculation. If CCTYP=CREOM, triples corrections based on
the method of moments approach may follow these steps.
The various types of triples corrections mentioned
below, and other information, can be found in the "Further
Information" section of this manual.
 state symmetry and state selection:
GROUP the name of the Abelian group to be used, which
may be only one of the groups shown in the
table below. The default is taken from $DATA,
and is reset to C1 if the group is nonAbelian.
The purpose is to let the Abelian symmetry be
turned off by setting GROUP=C1, if desired.
Symmetry is used to help with the initial
excited state selection, for controlling
the EOMCC calculations, and for labeling the
calculated states in the output (not to speed
up the calculations).
NSTATE an array of up to 8 integers telling how many
singlet excited states of each symmetry type
should be computed. The default is
NSTATE(1)=1,0,0,0,0,0,0,0 which means 1 excited
totally symmetric singlet state is to be found.
The ground state, which must lie in the totally
symmetric irrep due to use of an RHF reference
is always computed, and therefore should NOT
be included in the number of totally symmetric
excited states requested. There is no particular
reason to think the first excited state will be
totally symmetric, so most runs should give
NSTATE input. Up to 10 states can be found in
any irrep. Machine time is linear in the number
of states to be found, so be realistic about
how many states you solve for (particularly,
with multiroot solvers). The choice of
NSTATE(1)=0,0,0,0,0,0,0,0 means calculating the
ground state only, yielding the new types of
groundstate CRCCSD(T) corrections labeled as
types I, II, and III (see MTRIP).
irreducible representation symmetry table:
irrep 1 2 3 4 5 6 7 8
C1 A
C2 A B
Cs A' A''
Ci Ag Au
C2v A1 A2 B1 B2
C2h Ag Au Bg Bu
D2 A B1 B2 B3
D2h Ag Au B1g B1u B2g B2u B3g B3u
Note that this differs from $DET, $MCQDPT, etc!
IROOT selects the state whose energy is to be saved
for further calculations (default IROOT(1)=1,0).
The first integer lists the irrep number, from
the same table as NSTATE. The second lists
the number of the excited state. The default
corresponds to the ground state (labeled as
state 0), as this state must lie in the totally
symmetric representation. IROOT(1)=3,2 means
the second excited state of symmetry B1, if the
if the point group is C2v.
The energy of the state selected is stored as the energy
used for numerical derivative calculation, TRUDGE, etc.
The energy saved will be the EOMCCSD value unless the
triples correction are obtained, in which case the type
III energy will be saved (if available) or else the type
ID energy. If degenerate states are present, triples
are evaluated for only one such state, namely the one
with lower irrep number. The EOMCCSD energies will be
used to map an IROOT for a higher irrep number to this,
but if the triples corrections alter the order of the
states, the new IROOT may not pick up the state you are
interested in. Fixes: pick the lower irrep number, or
request states only in one symmetry type.
CCPRPE = a flag to select computation of the EOMCCSD level
excited state density matrices (see also CCPRP in
$CCINP for ground states). The computation takes
extra time, to obtain left eigenstates, so the
default is .FALSE.
Note: CCPRPE will evaluate excited states' dipole moments,
and the transition moments and oscillator strengths between
all states. This option can be chosen for CCTYP=EOMCCSD or
CREOM, with the latter doing triples corrections after the
SD level properties are obtained. Selecting this option,
or CCPRP in $CCINP, requires extra time due to solving for
the left eigenvectors (from the socalled "lambda"
equation). CVGEOM will affect the accuracy of the computed
properties. The resulting density matrices are square, not
symmetric, and at present cannot be used for any property
other than the dipole quantities. As a temporary
expedient, they are output in the PUNCH file for possible
use elsewhere.
 methods of converging the EOMCCSD equations and
selecting triples corrections to EOMCCSD energies:
MEOM selects the solver for the EOMCCSD calculations:
0 = one EOMCCSD root at a time, united iterative
space for all calculated roots (default)
1 = one root at a time, separate iterative space for
each calculated root
2 = the HiraoNakatsuji multiroot solver
3 = one root at a time, separate iterative space for
all computed right/left roots. (compare to 1)
4 = one root at a time, united iterative spaces
for each right/left root (compare to 0).
MEOM=0,1,2 obtain all the right eigenvectors first, and
then if properties are being computed, proceed to compute
the left eigenvectors. MEOM=3,4 obtain right and left
eigenvectors simultaneously, and therefore should only be
chosen if you are computing properties (see CCPRP/CCPRPE).
the next two apply only to CCTYP=CREOM:
MTRIP selects the type of noniterative triples
corrections to EOMCCSD energies:
1 = compute the CREOMCCSD(T) triples corrections
termed type I and II in the output. This is the
default, which skips the iterative CISD
calculations needed to construct the
CREOMCCSD(T) triples corrections of type III.
2 = after performing an additional CISD calculation,
evaluate all types of the CREOMCCSD(T) triples
corrections, including types I, II, and III.
This choice of MTRIP uses approximately 50 %
more memory, but less CPU time than MTRIP=4.
3 = evaluate the CREOMCCSD(T) corrections of type
III only. As with MTRIP=2, this calculation
includes the iterative CISD calculation, which
is needed to construct the type III triples
corrections, in addition to the EOMCCSD and
CREOMCCSD(T) calculations.
4 = carry out MTRIP=1 calculations, followed by
MTRIP=3 calculations, thus evaluating all types
of the CREOMCCSD(T) corrections (types I, II,
and III in the output). As with MTRIP=2, this
calculation includes the CISD iterations, which
are needed to construct the type III triples
corrections, in addition to the EOMCCSD and
CREOMCCSD(T) calculations. Compared to
MTRIP=2, this choice of MTRIP uses less memory,
but more CPU time.
MCI selects the solver for the CISD step, which
is irrelevant unless MTRIP is bigger than 1.
1 = one root at a time, separate iterative space for
each calculated root (default)
2 = the HiraoNakatsuji multiroot solver (slower)
 initial guess for the EOMCCSD and possible CISD steps:
MINIT selects the initial guess procedure for both the
EOMCCSD and CISD iterations (when MTRIP>1).
1 = (not a default, but HIGHLY RECOMMENDED). Use
EOMCCSd to start the EOMCCSD iterations and use
CISd to start the CISD iterations during the
CREOMCCSD(T), type III, calculations.
This means that the initial guesses for the
calculated states are defined using all single
excitations (letter S in EOMCCSd and CISd) and a
small subset of double excitations (the little d
in EOMCCSd and CISd) defined by active orbitals
or orbital range specified by the user. The
inclusion of a small set of active doubles
in addition to all singles in the initial guess
facilitates finding excited states characterized
by relatively large doubly excited amplitudes.
This choice of MINIT is strongly recommended.
(see NOACT, NUACT, and MOACT).
2 = Use CIS wave functions as initial guesses for
the EOMCCSD and possible CISD calculations.
This is the default, but may cause severe
convergence difficulties or even miss some
states entirely if the calculated states have
significant doubly excited character. MINIT=1 is
much better in these situations and strongly
recommended, particularly when there is a chance
of having lowlying states with nonnegligible
biexcited or multiconfigurational character.
the next three apply only to MINIT=1:
NOACT the number of occupied MOs in the active space
for the EOMCCSd and CISd initial guesses.
NUACT the number of unoccupied MOs in the active space
for the EOMCCSd and CISd initial guesses.
The NOACT and NUACT variables are used only by
MINIT=1, and are reset to 0 if MINIT=2.
There are no default values of NOACT and NUACT
and the user MUST provide NOACT and NUACT values
when MINIT=1. The values of NOACT and NUACT
should be small (5 or so), since they only
describe the numbers of highestenergy occupied
and lowestenergy unoccupied MOs that should
help to capture the leading orbital excitations
defining the excited states of interest (see an
example below). The user should make sure that
the active orbital range defined by NOACT and
NUACT does not fall across degenerate orbitals
(e.g., if NUACT is chosen such that only one of
the two degenerate pi orbitals is included in
the active orbital range for the EOMCCSd and
CISd initial guesses, the user should increase
NUACT at least by 1 to make sure that both pi
orbitals are included in the active orbital set).
See also the MOACT input for fine tuning.
MOACT array allowing explicit selection of the active
orbitals used to define the EOMCCSd and CISd
initial guesses. If not provided, the MOACT
array is filled such that the NOACT highest
occupied and NUACT lowest unoccupied orbitals
are selected. If MOACT array is given, the
number of values in it must equal NOACT+NUACT.
Sometimes, instead of defining larger NUACT
values that increase memory requirements for
the EOMCCSd and CISd initial guesses, it may be
helpful to specify the unoccupied orbitals,
since the lowest virtual orbitals of RHF,
whenever there are diffuse functions in the
basis set, may not be good at representing
valence excited states. Here is an example in
which the user is more selective about picking
active unoccupied orbitals for the EOMCCSd and
CISd initial guesses. In this example, the user
picks the highest 3 occupied and selected 5
unoccupied orbitals of RHF as active for a
30electron system (15 occupied orbitals total)
and at least 30 orbitals total:
MINIT=1 NOACT=3 NUACT=5
MOACT(1)=13,14,15, 19,20,24,25,30
 iteration control:
CVGEOM convergence criterion on the EOMCCSD excitation
amplitudes R1 and R2 (default=1.0d4).
MAXEOM maximum number of iterations in the EOMCCSD
calculations (default=50). For MEOM=0 or 1,
this is the maximum number of iterations per
each calculated state. For MEOM=2, this is
the maximum number of iterations for all
states of the EOMCCSD multiroot procedure.
MICEOM maximum number of microiterations in the
EOMCCSD calculations (default=80). Rarely used.
For MEOM=1 (separate iterative space for each
root), this is the maximum number of
microiterations for each calculated state.
For MEOM=0 or 2 (united iterative space
for all calculated roots), this is the
maximum number of microiterations for all
calculated states. It is much better to
perform calculations with MICEOM > MAXEOM
(i.e., in a single iteration cycle). If
for some reason the EOMCCSD convergence is
very slow and the iterative space becomes
very large, it may be worth changing the
default MICEOM value to MICEOM < MAXEOM
to reduce the disk usage. This is not
going to happen too often and normally there
is no need to change the default MICEOM value.
the next three apply only to CCTYP=CREOM, and only
if the triples method MTRIP is greater than 1:
CVGCI convergence criterion for the CISD expansion
coefficients (default=1.0d4).
MAXCI maximum number of iterations in the CISD
calculation (default=50). For MCI=1, this
is the maximum number of iterations per each
calculated CISD state. For MCI=2, this is
the maximum number of iterations for all
states of the CISD multiroot procedure.
MICCI maximum number of microiterations in the
CISD calculation (default=80). Rarely used.
For MCI=1 (separate iterative space for each
root), this is the maximum number of
microiterations for each calculated state.
For MCI=2 (united iterative space for all
calculated roots), this is the maximum
number of microiterations for all calculated
states. In analogy to MICEOM, it is much
better to perform the CISD calculations with
MICCI > MAXCI (i.e., in a single iteration
cycle).
==========================================================
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$MOPAC group (relevant if GBASIS=PM3, AM1, or MNDO)
This group affects only semiempirical jobs, which are
selected in $BASIS by keyword GBASIS.
PEPTID = flag for peptide bond correction.
By default a molecular mechanicsstyle torsion
potential term is added for every peptide bond
linkage found. The intent is to correct these
torsions to be closer to planar than they would
otherwise be in the semiempirical model. Here,
the peptide bond means any
O H
\\ /
CN
/ \
X
One such torsion is added for OCNH and one for
OCNX. This term is parameterized as in MOPAC6.
Default=.TRUE.
==========================================================
==========================================================
$GUESS group (optional, relevant for all SCFTYP's)
This group controls the selection of initial molecular
orbitals.
GUESS = Selects type of initial orbital guess.
= HUCKEL Carry out an extended Huckel calculation
using a Huzinaga MINI basis set, and
project this onto the current basis.
This is implemented for atoms up to Rn,
and will work for any all electron or
ECP basis set. (default for most runs)
= HCORE Diagonalize the one electron Hamiltonian
to obtain the initial guess orbitals.
This method is applicable to any basis
set, but does not work as well as the
HUCKEL guess.
= MOREAD Read in formatted vectors punched by an
earlier run. This requires a $VEC group,
and you MUST pay attention to NORB below.
= RDMINI Read in a $VEC group from a converged
calculation that used GBASIS=MINI and no
polarization functions, and project these
orbitals onto the current basis. Do not
use this option if the current basis
involve ECP basis sets.
= MOSAVED (default for restarts) The initial
orbitals are read from the DICTNRY file
of the earlier run.
= SKIP Bypass initial orbital selection. The
initial orbitals and density matrix are
assumed to be in the DICTNRY file. Mostly
used for RUNTYP=HESSIAN when the hessian
is being read in from the input.
= FMO Read orbitals from the DICTNRY file, from
previous FMO run with MODPRP=1.
All GUESS types except 'SKIP' permit reordering of the
orbitals, carry out an orthonormalization of the orbitals,
and generate the correct initial density matrix, for RHF,
UHF, ROHF, and GVB, but note that correct computation of
the GVB density requires also CICOEF in $SCF. The density
matrix cannot be generated from the orbitals alone for MP2,
CI, or MCSCF, so property evaluation for these should be
RUNTYP=ENERGY rather than RUNTYP=PROP using GUESS=MOREAD.
PRTMO = a flag to control printing of the initial guess.
(default=.FALSE.)
PUNMO = a flag to control punching of the initial guess.
(default=.FALSE.)
MIX = rotate the alpha and beta HOMO and LUMO orbitals
so as to generate inequivalent alpha and beta
orbital spaces. This pertains to UHF singlets
only. This may require use of NOSYM=1 in $CONTRL
depending on your situation. (default=.FALSE.)
NORB = The number of orbitals to be read in the $VEC
group. This applies only to GUESS=MOREAD.
For RHF, UHF, ROHF, and GVB, NORB defaults to the
number of occupied orbitals. NORB must be given for CI
and MCSCF. For UHF, if NORB is not given, only the
occupied alpha and beta orbitals should be given, back to
back. Otherwise, both alpha and beta orbitals must
consist of NORB vectors.
NORB may be larger than the number of occupied MOs, if you
wish to read in the virtual orbitals. If NORB is less
than the number of atomic orbitals, the remaining orbitals
are generated as the orthogonal complement to those read.
NORDER = Orbital reordering switch.
= 0 No reordering (default)
= 1 Reorder according to IORDER and JORDER.
IORDER = Reordering instructions.
Input to this array gives the new molecular
orbital order. For example, IORDER(3)=4,3 will
interchange orbitals 3 and 4, while leaving the
other MOs in the original order. This parameter
applies to all orbitals (alpha and beta) except
for UHF, where it only affects the alpha MOs.
(default is IORDER(i)=i )
JORDER = Reordering instructions.
Same as IORDER, but for the beta MOs of UHF.
INSORB = the first INSORB orbitals specified in the $VEC
group will be inserted into the Huckel guess,
making the guess a hybrid of HUCKEL/MOREAD. This
keyword is meaningful only when GUESS=HUCKEL, and
it is useful mainly for QM/MM runs where some
orbitals (buffer) are frozen and need to be
transferred to the initial guess vector set,
see $MOFRZ. (default=0)
* * * the next are 3 ways to clean up orbitals * * *
PURIFY = flag to symmetrize starting orbitals. This is the
most soundly based of the possible procedures.
However it may fail in complicated groups when the
orbitals are very unsymmetric. (default=.FALSE.)
TOLZ = level below which MO coefficients will be set
to zero. (default=1.0E7)
TOLE = level at which MO coefficients will be equated.
This is a relative level, coefficients are set
equal if one agrees in magnitude to TOLE times
the other. (default=5.0E5)
SYMDEN = project the initial density in order to generate
symmetric orbitals. This may be useful if the
HUCKEL or HCORE guess types give orbitals of
impure symmetry (?'s present). The procedure
will generate a fairly high starting energy, and
thus its use may not be a good idea for orbitals
of the quality of MOREAD. (default=.FALSE.)
==========================================================
==========================================================
$VEC group (optional, relevant for all SCFTYP's)
(required if GUESS=MOREAD)
This group consists of formatted vectors, as written
onto file PUNCH in a previous run. It is considered good
form to retain the titling comment cards punched before
the $VEC card, as a reminder to yourself of the origin of
the orbitals.
For Morokuma decompositions, the names of this group
are $VEC1, $VEC2, ... for each monomer, computed in the
identical orientation as the supermolecule. For transition
moment or spinorbit coupling runs, orbitals for states
one and possibly two are $VEC1 and $VEC2.
==========================================================
$MOFRZ group (optional, relevant for RHF, ROHF, GVB)
This group controls freezing the molecular orbitals
of your choice during the SCF procedure. If you choose
this option, select DIIS in $SCF since SOSCF will not
converge as well. GUESS=MOREAD is required in $GUESS.
FRZ = flag which triggers MO freezing. (default=.FALSE.)
IFRZ = an array of MOs in the input $VEC set which are
to be frozen. There is no default for this.
==========================================================
==========================================================
$STATPT group (for RUNTYP=OPTIMIZE or SADPOINT)
This group controls the search for stationary points.
Note that NZVAR in $CONTRL determines if the geometry
search is conducted in Cartesian or internal coordinates.
METHOD = optimization algorithm selection. Pick from
NR Straight NewtonRaphson iterate. This will
attempt to locate the nearest stationary
point, which may be of any order. There
is no steplength control. RUNTYP can be
either OPTIMIZE or SADPOINT
RFO Rational Function Optimization. This is
one of the augmented Hessian techniques
where the shift parameter(s) is(are) chosen
by a rational function approximation to
the PES. For SADPOINT searches it involves
two shift parameters. If the calculated
stepsize is larger than DXMAX the step is
simply scaled down to size.
QA Quadratic Approximation. This is another
version of an augmented Hessian technique
where the shift parameter is chosen such
that the steplength is equal to DXMAX.
It is completely equivalent to the TRIM
method. (default)
SCHLEGEL The quasiNR optimizer by Schlegel.
CONOPT, CONstrained OPTimization. An algorithm
which can be used for locating TSs.
The starting geometry MUST be a minimum!
The algorithm tries to push the geometry
uphill along a chosen Hessian mode (IFOLOW)
by a series of optimizations on hyperspheres
of increasingly larger radii.
Note that there currently are no restart
capabilitites for this method, not even
manually.
OPTTOL = gradient convergence tolerance, in Hartree/Bohr.
Convergence of a geometry search requires the
largest component of the gradient to be less
than OPTTOL, and the root mean square gradient
less than 1/3 of OPTTOL. (default=0.0001)
NSTEP = maximum number of steps to take. Restart data
is punched if NSTEP is exceeded. (default=20)
 the next four control the step size 
DXMAX = initial trust radius of the step, in Bohr.
For METHOD=RFO, QA, or SCHLEGEL, steps will
be scaled down to this value, if necessary.
(default=0.3 for OPTIMIZE and 0.2 for SADPOINT)
For METHOD=NR, DXMAX is inoperative.
For METHOD=CONOPT, DXMAX is the step along the
previous two points to increment the hypersphere
radius between constrained optimizations.
(default=0.1)
the next three apply only to METHOD=RFO or QA:
TRUPD = a flag to allow the trust radius to change as
the geometry search proceeds. (default=.TRUE.)
TRMAX = maximum permissible value of the trust radius.
(default=0.5 for OPTIMIZE and 0.3 for SADPOINT)
TRMIN = minimum permissible value of the trust radius.
(default=0.05)
 the next three control mode following 
IFOLOW = Mode selection switch, for RUNTYP=SADPOINT.
For METHOD=RFO or QA, the mode along which the
energy is maximized, other modes are minimized.
Usually refered to as "eigenvector following".
For METHOD=SCHLEGEL, the mode whose eigenvalue
is (or will be made) negative. All other
curvatures will be made positive.
For METHOD=CONOPT, the mode along which the
geometry is initially perturbed from the minima.
(default is 1)
In Cartesian coordinates, this variable doesn't
count the six translation and rotation degrees.
Note that the "modes" aren't from massweighting.
STPT = flag to indicate whether the initial geometry
is considered a stationary point. If .true.
the initial geometry will be perturbed by
a step along the IFOLOW normal mode with
stepsize STSTEP. (default=.false.)
The positive direction is taken as the one where
the largest component of the Hessian mode is
positive. If there are more than one largest
component (symmetry), the first is taken as
positive.
Note that STPT=.TRUE. has little meaning with
HESS=GUESS as there will be many degenerate
eigenvalues.
STSTEP = Stepsize for jumping off a stationary point.
Using values of 0.05 or more may work better.
(default=0.01)
IFREEZ = array of coordinates to freeze. These may be
internal or Cartesian coordinates. For example,
IFREEZ(1)=1,3 freezes the two bond lengths in
the $ZMAT example, while optimizing the angle.
If NZVAR=0, so that this value applies to the
Cartesian coordinates instead, the input of
IFREEZ(1)=4,7 means to freeze the x coordinates
if the 2nd and 3rd atoms in the molecule.
See also IFZMAT and FVALUE in $ZMAT, and IFCART
below, as IFREEZ does not apply to DLC internals.
In a numerical Hessian run, IFREEZ specifies
Cartesian displacements to be skipped for a
Partial Hessian Analysis. For more information:
J.D.Head, Int.J.Quantum Chem. 65, 827, 1997
H.Li, J.H.Jensen
Theoret. Chem. Acc. 107, 211219(2002)
IFCART = array of Cartesian coordinates to freeze during
a geometry optimization using delocalized internal
coordinates.
 The next two control the hessian matrix quality 
HESS = selects the initial hessian matrix.
= GUESS chooses a positive definite diagonal
hessian. (default for RUNTYP=OPTIMIZE)
= READ causes the hessian to be read from a $HESS
group. (default for RUNTYP=SADPOINT)
= RDAB reads only the ab initio part of the
hessian, and approximates the effective
fragment blocks.
= RDALL reads the full hessian, then converts
any fragment blocks to 6x6 T+R shape.
(this option is seldom used).
= CALC causes the hessian to be computed, see
the $FORCE group.
IHREP = the number of steps before the hessian is
recomputed. If given as 0, the hessian will
be computed only at the initial geometry if
you choose HESS=CALC, and never again. If
nonzero, the hessian is recalculated every
IHREP steps, with the update formula used on
other steps. (default=0)
HSSEND = a flag to control automatic hessian evaluation
at the end of a successful geometry search.
(default=.FALSE.)
 the next two control the amount of output 
Let 0 mean the initial geometry, L mean the last
geometry, and all mean every geometry.
Let INTR mean the internuclear distance matrix.
Let HESS mean the approximation to the hessian.
Note that a directly calculated hessian matrix
will always be punched, NPUN refers only to the
updated hessians used by the quasiNewton step.
NPRT = 1 Print INTR at all, orbitals at all
0 Print INTR at all, orbitals at 0+L (default)
1 Print INTR at all, orbitals never
2 Print INTR at 0+L, orbitals never
NPUN = 3 Punch all orbitals and HESS at all
2 Punch all orbitals at all
1 same as 0, plus punch HESS at all
0 Punch all orbitals at 0+L, otherwise only
occupied orbitals (default)
1 Punch occ orbitals at 0+L only
2 Never punch orbitals
 the following parameters are quite specialized 
PURIFY = a flag to help eliminate the rotational and
translational degrees of freedom from the
initial hessian (and possibly initial gradient).
This is much like the variable of the same name
in $FORCE, and will be relevant only if internal
coordinates are in use. (default=.FALSE.)
PROJCT = a flag to eliminate translation and rotational
degrees of freedom from Cartesian optimizations.
The default is .TRUE. since this normally will
reduce the number of steps, except that this
variable is set false when POSITION=FIXED is
used during EFP runs.
ITBMAT = number of microiterations used to compute the
step in Cartesians which corresponds to the
desired step in internals. The default is 5.
UPHESS = SKIP do not update Hessian (not recommended)
BFGS default for OPTIMIZE using RFO or QA
POWELL default for OPTIMIZE using NR or CONOPT
POWELL default for SADPOINT
MSP mixed MurtaghSargent/Powell update
SCHLEGEL only choice for METHOD=SCHLEGEL
MOVIE = a flag to create a series of structural data
which can be show as a movie by the MacIntosh
program Chem3D. The data is written to the
file IRCDATA. (default=.FALSE.)
 NNEG, RMIN, RMAX, RLIM apply only to SCHLEGEL 
NNEG = The number of negative eigenvalues the force
constant matrix should have. If necessary the
smallest eigenvalues will be reversed. The
default is 0 for RUNTYP=OPTIMIZE, and 1 for
RUNTYP=SADPOINT.
RMIN = Minimum distance threshold. Points whose root
mean square distance from the current point is
less than RMIN are discarded. (default=0.0015)
RMAX = Maximum distance threshold. Points whose root
mean square distance from the current point is
greater than RMAX are discarded. (default=0.1)
RLIM = Linear dependence threshold. Vectors from the
current point to the previous points must not
be colinear. (default=0.07)
==========================================================
* * * * * * * * * * * * * * * * * * * * *
See the 'further information' section for
some help with OPTIMIZE and SADPOINT runs
* * * * * * * * * * * * * * * * * * * * *
==========================================================
$TRUDGE group (required for RUNTYP=TRUDGE)
This group defines the parameters for a nongradient
optimization of exponents or the geometry. The TRUDGE
package is a modified version of the same code from Michel
Dupuis' HONDO 7.0 system, origially written by H.F.King.
Presently the program allows for the optimization of 10
parameters.
Exponent optimization works only for uncontracted
primitives, without enforcing any constraints. Two
nonsymmetry equivalent H atoms would have their p
function exponents optimized separately, and so would two
symmetry equivalent atoms! A clear case of GIGO.
Geometry optimization works only in HINT internal
coordinates (see $CONTRL and $DATA groups). The total
energy of all types of SCF wavefunctions can be optimized,
although this would be extremely stupid as gradient
methods are far more efficient. The main utility is for
open shell MP2 or CI geometry optimizations, which may
not be done in any other way with GAMESS. If your run
requires NOSYM=1 in $CONTRL, you must be sure to use only
C1 symmetry in the $DATA group.
OPTMIZ = a flag to select optimization of either geometry
or exponents of primitive gaussian functions.
= BASIS for basis set optimization.
= GEOMETRY for geometry optimization (default).
This means minima search only, there is no saddle
point capability.
NPAR = number of parameters to be optimized.
IEX = defines the parameters to be optimized.
If OPTMIZ=BASIS, IEX declares the serial number
of the Gaussian primitives for which the exponents
will be optimized.
If OPTMIZ=GEOMETRY, IEX define the pointers to
the HINT internal coordinates which will be optimized.
(Note that not all internal coordinates have to be
optimized.) The pointers to the internal coordinates
are defined as: (the number of atom on the input
list)*10 + (the number of internal coordinate for that
atom). For each atom, the HINT internal coordinates
are numbered as 1, 2, and 3 for BOND, ALPHA, and BETA,
respectively.
P = Defines the initial values of the parameters to be
optimized. You can use this to reset values given
in $DATA. If omitted, the $DATA values are used.
If given here, geometric data must be in Angstroms
and degrees.
A complete example is a TCSCF multireference 631G
geometry optimization for methylene,
$CONTRL SCFTYP=GVB CITYP=GUGA RUNTYP=TRUDGE
COORD=HINT $END
$BASIS GBASIS=N31 NGAUSS=6 $END
$DATA
Methylene TCSCF+CISD geometry optimization
Cnv 2
C 6. LC 0.00 0.0 0.00  O K
H 1. PCC 1.00 53. 0.00 + O K I
$END
$SCF NCO=3 NPAIR=1 $END
$TRUDGE OPTMIZ=GEOMETRY NPAR=2
IEX(1)=21,22 P(1)=1.08 $END
$CIDRT GROUP=C2V SOCI=.TRUE. NFZC=1 NDOC=3 NVAL=1
NEXT=1 $END
using GVBPP(1), or TCSCF orbitals in the CI. The starting
bond length is reset to 1.09, while the initial angle will
be 106 (twice 53). Result after 17 steps is R=1.1283056,
halfangle=51.83377, with a CI energy of 38.9407538472
Note that you may optimize the geometry for an excited
CI state, just specify
$GUGDIA NSTATE=5 $END
$GUGDM IROOT=3 $END
to find the equilibrium geometry of the third state (of
five total states) of the symmetry implied by your $CIDRT.
==========================================================
==========================================================
$TRURST group (optional, relevant for
RUNTYP=TRUDGE)
This group specifies restart parameters for TRUDGE
runs and accuracy thresholds.
KSTART indicates the conjugate gradient direction in which
the optimization will proceed. ( default = 1 )
1 .... indicates that this is a nonrestart run.
0 .... corresponds to a restart run.
FNOISE accuracy of function values.
Variation smaller than FNOISE are not considered to be
significant (Def. 0.0005)
TOLF accuracy required of the function (Def. 0.001)
TOLR accuracy required of conjugate directions (Def. 0.05)
For geometry optimization, the values which give
better results (closer to the ones obtained with gradient
methods) are: TOLF=0.0001, TOLR=0.001, FNOISE=0.00001
==========================================================
==========================================================
$FORCE group
(optional, relevant for RUNTYP=HESSIAN,OPTIMIZE,SADPOINT)
This group controls the computation of the hessian
matrix (the energy second derivative tensor, also known
as the force constant matrix), and an optional harmonic
vibrational analysis. This can be a very time consuming
calculation. However, given the force constant matrix,
the vibrational analysis for an isotopically substituted
molecule is very cheap. Related input is HESS= in
$STATPT, and the $MASS, $HESS, $GRAD, $DIPDR, $VIB groups.
Calculation of the hessian automatically yields the dipole
derivative tensor, giving IR frequencies. Raman
intensities are obtained by following with RUNTYP=RAMAN.
METHOD = chooses the computational method:
= ANALYTIC is a fully analytic calculation. This is
implemented only for SCFTYP=RHF, ROHF,
GVB (when NPAIR is 0 or 1), and MCSCF
(for determinants, CISTEP=ALDET only).
This is the default for these cases.
= SEMINUM does numerical differentiation of
analytically computed first derivatives.
This is the default for UHF, MCSCF using
other CISTEPs, DFT, all solvent,
models, relativistic corrections, and
most MP2 or CI runs.
= FULLNUM numerically twice differentiates the
energy, which can be used by all other
cases. It requires many energies (a
check run will tell how many) and so
it is mainly useful for systems with
only very few symmetry unique atoms.
The default for METHOD is to pick ANALYTIC over SEMINUM if
that is programmed, and SEMINUM otherwise. FULLNUM will
never be chosen unless you specifically request it.
RDHESS = a flag to read the hessian from a $HESS group,
rather than computing it. This variable pertains
only to RUNTYP=HESSIAN. See also HESS= in the
$STATPT group. (default is .FALSE.)
PURIFY = controls cleanup
Given a $ZMAT, the hessian and dipole derivative
tensor can be "purified" by transforming from
Cartesians to internals and back to Cartesians.
This effectively zeros the frequencies of the
translation and rotation "modes", along with
their IR intensities. The purified quantities
are punched out. Purification does change the
Hessian slightly, frequencies at a stationary
point can change by a wave number or so. The
change is bigger at nonstationary points.
(default=.FALSE. if $ZMAT is given)
PRTIFC = prints the internal coordinate force constants.
You MUST have defined a $ZMAT group to use this.
(Default=.FALSE.)
 the next four apply to numeric differentiation 
NVIB = The number of displacements in each Cartesian
direction for force field computation. This
pertains only to SEMINUM, as FULLNUM always
uses double difference formulae.
= 1 Move one VIBSIZ unit in each positive
Cartesian direction. This requires 3N+1
evaluations of the wavefunction, energy, and
gradient, where N is the number of SYMMETRY
UNIQUE atoms given in $DATA. (default)
= 2 Move one VIBSIZ unit in the positive direction
and one VIBSIZ unit in the negative direction.
This requires 6N+1 evaluations of the
wavefunction and gradient, and gives a small
improvement in accuracy. In particular, the
frequencies will change from NVIB=1 results by
no more than 10100 wavenumbers, and usually
much less. However, the normal modes will be
more nearly symmetry adapted, and the residual
rotational and translational "frequencies"
will be much closer to zero.
VIBSIZ = Displacement size (in Bohrs). This pertains to
Both SEMINUM and FULLNUM. Default=0.01
Let 0 mean the Vib0 geometry, and
D mean all the displaced geometries
NPRT = 1 Print orbitals at 0 and D
= 0 Print orbitals at 0 only (default)
NPUN = 2 Punch all orbitals at 0 and D
= 1 Punch all orbitals at 0 and occupied orbs at D
= 0 Punch all orbitals at 0 only (default)
 the rest control normal coordinate analysis 
VIBANL = flag to activate vibrational analysis.
(the default is .TRUE. for RUNTYP=HESSIAN, and
otherwise is .FALSE.)
SCLFAC = scale factor for vibrational frequencies, used
in calculating the zero point vibrational energy.
Some workers correct for the usual overestimate
in SCF frequencies by a factor 0.89. ZPE or other
methods might employ other factors, see A.P.Scott,
L.Radom J.Phys.Chem. 100, 1650216513 (1996).
The output always prints unscaled frequencies, so
this value is used only during the thermochemical
analysis. (Default is 1.0)
TEMP = an array of up to ten temperatures at which the
thermochemistry should be printed out. The
default is a single temperature, 298.15 K. To
use absolute zero, input 0.001 degrees.
FREQ = an array of vibrational frequencies. If the
frequencies are given here, the hessian matrix
is not computed or read. You enter any imaginary
frequencies as negative numbers, omit the
zero frequencies corresponding to translation
and rotation, and enter all true vibrational
frequencies. Thermodynamic properties will be
printed, nothing else is done by the run.
PRTSCN = flag to print contribution of each vibrational
mode to the entropy. (Default is .FALSE.)
DECOMP = activates internal coordinate analysis.
Vibrational frequencies will be decomposed into
"intrinsic frequencies", by the method of
J.A.Boatz and M.S.Gordon, J.Phys.Chem., 93,
18191826(1989). If set .TRUE., the $ZMAT group
may define more than 3N6 (3N5) coordinates.
(default=.FALSE.)
PROJCT = controls the projection of the hessian matrix.
The projection technique is described by
W.H.Miller, N.C.Handy, J.E.Adams in J. Chem.
Phys. 1980, 72, 99112. At stationary points,
the projection simply eliminates rotational and
translational contaminants. At points with
nonzero gradients, the projection also ensures
that one of the vibrational modes will point
along the gradient, so that there are a total of
7 zero frequencies. The other 3N7 modes are
constrained to be orthogonal to the gradient.
Because the projection has such a large effect on
the hessian, the hessian punched is the one
BEFORE projection. For the same reason, the
default is .FALSE. to skip the projection, which
is mainly of interest in dynamical calculations.
==========================================================
There is a set of programs for the calculation of kinetic
or equilibrium isotope effects from the group of Piotr
Paneth at the University of Lodz. The ISOEFF program
accepts data from GAMESS, and can be obtained from
paneth@p.lodz.pl.
==========================================================
$CPHF group (relevant for analytic RUNTYP=HESSIAN)
This group controls the solution of the response
equations, also known as coupled HartreeFock.
POLAR = a flag to request computation of the static
polarizability, alpha. Because this property
needs 3 additional response vectors, beyond those
needed for the hessian, the default is to skip the
property. (default = .FALSE.)
CPHF = MO forms response equations from transformed MO
Integrals. (default)
= AO forms response equations from AO integrals,
which takes less memory, and is programmed only
for RHF wavefunctions.
NWORD = controls memory usage for this step. The default
uses all available memory. (default=0)
==========================================================
$MASS group (relevant for RUNTYP=HESSIAN, IRC, or DRC)
This group permits isotopic substitution during the
computation of mass weighted Cartesian coordinates. Of
course, the masses affect the frequencies and normal modes
of vibration.
AMASS = An array giving the atomic masses, in amu. The
default is to use the mass of the most abundant
isotope. Masses through element 104 are stored.
example  $MASS AMASS(3)=2.0140 $END
will make the third atom in the molecule a deuterium.
==========================================================
==========================================================
$HESS group
(relevant for RUNTYP=HESSIAN if RDHESS=.TRUE.)
(relevant for RUNTYP=IRC if FREQ,CMODE not given)
(relevant for RUNTYP=OPTIMIZE,SADPOINT if HESS=READ)
Formatted force constant matrix (FCM), i.e. hessian
matrix. This data is punched out by a RUNTYP=HESSIAN job,
in the correct format for subsequent runs. The first card
in the group must be a title card.
A $HESS group is always punched in Cartesians. It
will be transformed into internal coordinate space if a
geometry search uses internals. It will be mass weighted
(according to $MASS) for IRC and frequency runs.
The initial FCM is updated during the course of a
geometry optimization or saddle point search, and will be
punched if a run exhausts its time limit. This allows
restarts where the job leaves off. You may want to read
this FCM back into the program for your restart, or you
may prefer to regenerate a new initial hessian. In any
case, this updated hessian is absolutely not suitable for
frequency prediction!
==========================================================
$GRAD group (relevant for RUNTYP=OPTIMIZE or SADPOINT)
(relevant for RUNTYP=HESSIAN when RDHESS=.TRUE.)
Formatted gradient vector at the $DATA geometry. This
data is read in the same format it was punched out.
For RUNTYP=HESSIAN, this information is used to
determine if you are at a stationary point, and possibly
for projection. If omitted, the program pretends the
gradient is zero, and otherwise proceeds normally.
For geometry searches, this information (if known) can
be read into the program so that the first step can be
taken instantly.
==========================================================
==========================================================
$DIPDR group (relevant for RUNTYP=HESSIAN if RDHESS=.T.)
Formatted dipole derivative tensor, punched in a previous
RUNTYP=HESSIAN job. If this group is omitted, then a
vibrational analysis will be unable to predict the IR
intensities, but the run can otherwise proceed.
==========================================================
$VIB group (relevant for RUNTYP=HESSIAN, METHOD=SEMINUM)
Formatted card image restart data. This data is
read in the format it was punched by a previous HESSIAN
job to the file IRCDATA. Just add a " $END" card, and if
the final gradient was punched as zero, delete the last
set of data. Normally, IREST in $CONTRL will NOT be used
in conjunction with a HESSIAN restart. The mere presence
of this deck triggers the restart from cards. This deck
can also be used to turn a single point differencing run
into double differencing, as well as recovering from time
limits, or other bombouts.
==========================================================
$VIB2 group (relevant for RUNTYP=HESSIAN, METHOD=FULLNUM)
Formatted restart information, consisting of energy values.
Just add a " $END" line at the bottom, and place this group
into the input file to effect a restart.
==========================================================
==========================================================
$IRC group (relevant for RUNTYP=IRC)
This group governs the location of the intrinsic
reaction coordinate, a steepest descent path in mass
weighted corrdinates, that connects the saddle point to
reactants and products.
 there are five integration methods chosen by PACE.
PACE = GS2 selects the GonzalezSchlegel second order
method. This is the default method.
Related input is:
GCUT cutoff for the norm of the massweighted gradient
tangent (the default is chosen in the range from
0.00005 to 0.00020, depending on the value for
STRIDE chosen below.
RCUT cutoff for Cartesian RMS displacement vector.
(the default is chosen in the range 0.0005 to
0.0020 Bohr, depending on the value for STRIDE)
ACUT maximum angle from end points for linear
interpolation (default=5 degrees)
MXOPT maximum number of contrained optimization steps
for each IRC point (default=20)
IHUPD is the hessian update formula. 1 means Powell,
2 means BFGS (default=2)
GA is a gradient from the previous IRC point, and is
used when restarting.
OPTTOL is a gradient cutoff used to determine if the IRC
is approaching a minimum. It has the same meaning
as the variable in $STATPT. (default=0.0001)
PACE = LINEAR selects linear gradient following (Euler's
method). Related input is:
STABLZ switches on Ishida/Morokuma/Komornicki reaction
path stabilization. The default is .TRUE.
DELTA initial step size along the unit bisector, if
STABLZ is on. Default=0.025 Bohr.
ELBOW is the collinearity threshold above which the
stabilization is skipped. If the mass weighted
gradients at QB and QC are almost collinear, the
reaction path is deemed to be curving very little,
and stabilization isn't needed. The default is
175.0 degrees. To always perform stabilization,
input 180.0.
READQB,EB,GBNORM,GB are energy and gradient data
already known at the current IRC point. If it
happens that a run with STABLZ on decides to skip
stabilization because of ELBOW, this data will be
punched to speed the restart.
PACE = QUAD selects quadratic gradient following.
Related input is:
SAB distance to previous point on the IRC.
GA gradient vector at that historical point.
PACE = AMPC4 selects the fourth order AdamsMoulton
variable step predictorcorrector.
Related input is:
GA0,GA1,GA2 which are gradients at previous points.
PACE = RK4 selects the 4th order RungeKutta variable
step method. There is no related input.
 The next two are used by all PACE choices 
STRIDE = Determines how far apart points on the reaction
path will be. STRIDE is used to calculate the
step taken, according to the PACE you choose.
The default is good for the GS2 method, which is
very robust. Other methods should request much
smaller step sizes, such as 0.10 or even 0.05.
(default = 0.30 sqrt(amu)Bohr)
NPOINT = The number of IRC points to be located in this
run. The default is to find only the next point.
(default = 1)
 The next two let you choose your output volume 
Let F mean the first IRC point found in this run,
and L mean the final IRC point of this run.
Let INTR mean the internuclear distance matrix.
NPRT = 1 Print INTR at all, orbitals at all IRC points
0 Print INTR at all, orbitals at F+L (default)
1 Print INTR at all, orbitals never
2 Print INTR at F+L, orbitals never
NPUN = 1 Punch all orbitals at all IRC points
0 Punch all orbitals at F+L, only occupied
orbitals at IRC points between (default)
1 Punch all orbitals at F+L only
2 Never punch orbitals
 The next two tally the reaction path results. The
defaults are appropriate for starting from a saddle
point, restart values are automatically punched out.
NEXTPT = The number of the next point to be computed.
STOTAL = Total distance along the reaction path to next
IRC point, in mass weighted Cartesian space.
 The following controls jumping off the saddle point.
If you give a $HESS group, FREQ and CMODE will be
generated automatically.
SADDLE = A logical variable telling if the coordinates
given in the $DATA deck are at a saddle point
(.TRUE.) or some other point lying on the IRC
(.FALSE.). If SADDLE is true, either a $HESS
group or else FREQ and CMODE must be given.
(default = .FALSE.) Related input is:
TSENGY = A logical variable controlling whether the energy
and wavefunction are evaluated at the transition
state coordinates given in $DATA. Since you
already know the energy from the transition state
search and force field runs, the default is .F.
FORWRD = A logical variable controlling the direction to
proceed away from a saddle point. The forward
direction is defined as the direction in which
the largest magnitude component of the imaginary
normal mode is positive. (default =.TRUE.)
EVIB = Desired decrease in energy when following the
imaginary normal mode away from a saddle point.
(default=0.0005 Hartree)
FREQ = The magnitude of the imaginary frequency, given
in cm**1.
CMODE = An array of the components of the normal mode
whose frequency is imaginary, in Cartesian
coordinates. Be careful with the signs!
You must give FREQ and CMODE if you don't give a $HESS
group, when SADDLE=.TRUE. The option of giving these
two variables instead of a $HESS does not apply to the
GS2 method, which must have a hessian input, even for
restarts. Note also that EVIB is ignored by GS2 runs.
==========================================================
* * * * * * * * * * * * * * * * * *
For hints about IRC tracking, see
the 'further information' section.
* * * * * * * * * * * * * * * * * *
==========================================================
$VSCF group (optional, relevant to RUNTYP=VSCF)
This group governs the computation of vibrational
frequencies including anharmonic effects. Besides the
keywords shown below, the input file must contain a $HESS
group (and perhaps a $DIPDR group), to start with
previously obtained harmonic vibrational information. The
VSCF method requires only energies, so any energy type in
GAMESS may be used, perhaps with fully numerical harmonic
vibrational information. Energies are sampled along the
directions of the harmonic normal modes, and usually along
pairs of harmonic normal modes, after which the nuclear
vibrational wavefunctions are obtained. The dipole on the
grid points may be used to give improved IR intensities.
The most accurate calculation would compute the
potential surface directly, on all grid points, but this
involves many energy evaluations. An attractive
alternative is the Quartic Force Field approximation of
Yagi et al., which computes a fit to the derivatives up to
fourth order by computing a specialized set of points,
after which this fit is used to generate the full grid of
points for the solver.
Vibrational wavefunctions are obtained at an SCFlike
level, termed VSCF, using product nuclear wavefunctions,
along with an MP2like correction to the vibrational
energy, which is termed correlation corrected (ccVSCF).
In addition, vibrational energy levels based on second
order degenerate pertubation theory (see VDPT) or a CI
analog (see VCI) may be obtained.
Restarts involve the $VIBSCF group (which has different
formats for each PETYP), and the READV keyword. Restarts
are safest on the same machine, where normal mode phases
are reproducible.
References for the VSCF method, the QFF approximation,
and the solvers are given in Chapter 4 of this manual,
along with a number of sample applications.
PETYP = DIRECT computes the full potential energy surface,
according to NCOUP/NGRID. The total number
of energy/dipole calculations for NCOUP=2
will be M*NGRID + (M*(M1)/2)*NGRID*NGRID,
where M is the number of normal modes.
= QFF the Quartic Force Field approximation to
the potential surface is obtained. This is
usually only slightly less accurate, but
has a greatly reduced computational burden,
namely 6*M + 12*M*(M1)/2 energy/dipoles.
NCOUP = the order of mode couplings included.
= 1 computes 1D grids along each harmonic mode
= 2 adds additionally, 2D grids along each pair
of normal modes. (default=2)
NGRID = number of grid points to be used in solving for
the anharmonic vibrational levels. In the case
of PETYP=DIRECT, each of these grid points must be
explicitly computed. For PETYP=QFF these grid
points are obtained from a fitted quartic force
field. Reasonable values are 8 or 16 for DIRECT,
with 16 considered significantly more accurate.
For PETYP=QFF, the generation of the solver grid
is very fast, so use 16 always. (default=16)
STPSZ = step size for PETYP=QFF displacements. The
step along each mode depends on the harmonic
frequency, as well as this parameter, whose
default is usually satisfactory (default=0.5)
The next keywords relate to the solver for the vibrational
states. The results always include VSCF and ccVSCF (SCF
and nondegenerate MP2like solutions). Use of the restart
option makes comparing the solvers very fast, compared to
the time to generate the surface energy points.
VDPT = option to use 2nd order degenerate perturbation
theory, based on the ground and singly excited
vibrational levels. Results for virtual CI within
the same singly excited space will also be given.
(default=.TRUE.)
VCI = option to use the virtual CI solver within a space
of the ground and both singly and doubly excited
vibrational levels. Selection of VCI turns VDPT
off. (default=.FALSE.)
The solver finds the ground vibrational state (v=0) by
default, but will rapidly find excited levels (such as all
v=1) if restarted (see READV). Note that IEXC is one
greater than the sum of the vibrational quantum numbers.
IEXC = 1 obtain fundamental frequencies (default)
= 2 instead, obtain first overtones
= 3 instead, obtain second overtones
ICAS1, ICAS2 = starting and ending vibrations whose quanta
are included. The default is all modes, ICAS1=1
and ICAS2=3N6 (or 3N5).
SFACT = a numerical cutoff for small contributions in
the solver. The default is 1d5.
VCFCT = scaling factor for paircoupling potential.
Sometimes when paircoupling potential values
are larger than the corresponding single mode
values, they must be scaled down. (Default=1.0)
The next two relate to simplified intensity computation.
These simplifications are aimed at speeding up MP2 runs, if
one does not care so much about intensities, and would like
to eliminate the considerable extra time to compute MP2
level dipoles. It is pointless to select DMDR for SCF
electronic structure, where the dipoles are very fast.
DMDR must not be used if overtones are being computed.
DMDR = if true, indicates that the harmonic dipole
derivative tensor $DIPDR is input, rather than
computing the dipoles. (default is .FALSE.)
MPDIP = for MP2 electronic structure, a value of .FALSE.
uses SCF level dipoles in order to save the time
needed to obtain the MP2 density at every grid
point. It is more accurate to use the DMDR flag
instead of this option, if $DIPDR is available.
Obviously this variable is irrelevant for SCF
level electronic structure. (default=.TRUE.)
IMODE = array of modes for which anharmonic effects will
be computed. IMODE(1)=10,19 computes anharmonic
energies and wavefunctions for modes 10 and 19,
only. In the current implementation, pairs of
modes cannot be coupled, so NCOUP is forced to 1
if this option is specified. This approximation
is intended for larger molecules, where the whole
VSCF calculation is prohibitive.
PROJCT = controls the projection of the hessian matrix
(same meaning as in $FORCE). Default is .FALSE.,
but is .TRUE. if IFREEZ is specified in $STATPT.
READV = flag to indicate restart data $VIBSCF should be
read in to resume an interrupted calculation, or
to obtain overtones in followon runs. $VIBSCF's
contents are different for PETYP=DIRECT or QFF.
(default is .FALSE.)
==========================================================
$VIBSCF group (optional, relevant to RUNTYP=VSCF)
This is restart data, as written to file IRCDATA in a
partially completed previous run. Append a " $END" line,
and select READV=.TRUE. to read the data.
==========================================================
==========================================================
$DRC group (relevant for RUNTYP=DRC)
This group governs the dynamical reaction coordinate,
a classical trajectory method based on quantum chemical
potential energy surfaces. In GAMESS these may be either
ab initio or semiempirical. Because the vibrational
period of a normal mode with frequency 500 wavenumbers is
67 fs, a DRC needs to run for many steps in order to
sample a representative portion of phase space. Almost
all DRCs break molecular symmetry, so build your molecule
with C1 symmetry in $DATA, or specify NOSYM=1 in $CONTRL.
Restart data can be found in the job's OUTPUT file, with
important results summarized to the IRCDATA file.
NSTEP = The number of DRC points to be calculated, not
including the initial point. (default = 1000)
DELTAT = is the time step. (default = 0.1 fs)
TOTIME = total duration of the DRC computed in a previous
job, in fs. The default is the correct value
when initiating a DRC. (default=0.0 fs)
* * *
In general, a DRC can be initiated anywhere,
so $DATA might contain coordinates of the
equilibrium geometry, or a nearby transition
state, or something else. You must also
supply an initial kinetic energy, and the
direction of the initial velocity, for which
there are a number of options:
EKIN = The initial kinetic energy (default = 0.0
kcal/mol)
See also ENM, NVEL, and VIBLVL regarding alternate
ways to specify the initial value.
VEL = an array of velocity components, in Bohr/fs.
When NVEL is false, this is simply the direction
of the velocity vector. Its magnitude will be
automatically adjusted to match the desired
initial
kinetic energy, and it will be projected so that
the translation of the center of mass is removed.
Give in the order vx1, vy1, vz1, vx2, vy2, ...
NVEL = a flag to compute the initial kinetic energy from
the input VEL using the sum of mass*VEL*VEL/2.
This flag is usually selected only for restarts.
(default=.FALSE.)
The next three allow the kinetic energy to be
partitioned over all normal modes. The
coordinates in $DATA are likely to be from
a stationary point! You must also supply a
$HESS group, which is the nuclear force constant
matrix at the starting geometry.
VIBLVL = a flag to turn this option on (default=.FALSE.)
VIBENG = an array of energies (in units of multiples of
the hv of each mode) to be imparted along each
normal mode. The default is to assign the zero
point energy only, VIBENG(1)=0.5, 0.5, ..., 0.5
when HESS=MIN, and 0.0, 0.5, ..., 0.5 if HESS=TS.
If given as a negative number, the initial
direction of the velocity vector is along the
reverse direction of the mode. "Reverse" means
the phase of the normal mode is chosen such that
the largest magnitude component is a negative
value. An example might be VIBENG(4)=2.5 to add
two quanta to mode 4, along with zero point
energy in all modes.
RCENG = reaction coordinate energy, in kcal/mol. This is
the initial kinetic energy given to the imaginary
frequency normal mode when HESS=TS. If this is
given as a negative value, the direction of the
velocity vector will be the "reverse direction",
meaning the phase of the normal mode will be
chosen so its largest component is negative.
* * *
The next two pertain to initiating the DRC along
a single normal mode of vibration. No kinetic
energy is assigned to the other modes. You must
also supply a $HESS group at the initial geometry.
NNM = The number of the normal mode to which the initial
kinetic energy is given. The absolute value of NNM
must be in the range 1, 2, ..., 3N6. If NNM is a
positive/negative value, the initial velocity will
lie in the forward/reverse direction of the mode.
"Forward" means the largest normal mode component
is a positive value. (default=0)
ENM = the initial kinetic energy given to mode NNM,
in units of vibrational quanta hv, so the amount
depends on mode NNM's vibrational frequency, v.
If you prefer to impart an arbitrary initial
kinetic energy to mode NNM, specify EKIN instead.
(default = 0.0 quanta)
To summarize, there are 5 ways to initiate a trajectory:
1. VEL vector with NVEL=.TRUE. This is difficult to
specify at your initial point, and so this option
is mainly used when restarting your trajectory.
The restart information is always in this format.
2. VEL vector and EKIN with NVEL=.FALSE. This will
give a desired amount of kinetic energy in the
direction of the velocity vector.
3. VIBLVL and VIBENG and possibly RCENG, to give some
initial kinetic energy to all normal modes.
4. NNM and ENM to give quanta to a single normal mode.
5. NNM and EKIN to give arbitrary kinetic energy to
a single normal mode.
* * *
The most common use of the next two is to analyze
a trajectory with respect to the normal modes of
a minimum energy geometry it travels around.
NMANAL = a flag to select mapping of the massweighted
Cartesian DRC coordinates and velocity (conjugate
momentum) in terms of normal modes at a nearby
reference stationary point (which can be either a
minimum or transition state). This reference
geometry could in fact be the same as the initial
point of the DRC, but does not need to be.
If you choose this option, you must supply C0,
HESS2, and a $HESS2 group corresponding to the
reference stationary point. (default=.FALSE.)
C0 = an array of the coordinates of the stationary
reference point (the coordinates in $DATA might
well be some other coordinates). Give in the
order x1,y1,z1,x2,y2,... in Angstroms.
* * *
The next options apply to input choices which may
read a $HESS at the initial DRC point, namely NNM
or VIBLVL, or to those that read a $HESS2 at some
reference geometry (NMANAL).
HESS = MIN indicates the hessian supplied for the initial
geometry corresponds to a minimum (default).
= TS indicates the hessian is for a saddle point.
HESS2 = MIN (default) or TS, the same meaning, for the
reference geometry.
These are used to decide if modes 16 (minimum) or
modes 27 (TS) are to be excluded from the hessian
as the translational and rotational contaminants.
If the initial and reference geometries are the same,
these two hessians will be duplicates of each other.
The next variables can cause termination of a run, if
molecular fragments get too far apart or close together.
NFRGPR = Number of atom pairs whose distance will be
checked. (default is 0)
IFRGPR = Array of the atom pairs. 2 times NFRGPR values.
FRGCUT = Array for a boundary distance (in Bohr) for atom
pairs to end DRC calculations. The run will
stop if any distance exceeds the tolerance, or if
a value is given as a negative number, if the
distance becomes shorter than the absolute value.
In case the trajectory starts outside the bounds
specified, they do not apply until after the
trajectory reaches a point where the criteria
are satisfied, and then goes outside again.
Give NFRGPR values.
* * *
The final variables control the volume of output.
Let F mean the first DRC point found in this run,
and L mean the last DRC point of this run.
NPRTSM = summarize the DRC results every NPRTSM steps,
to the file IRCDATA. (default = 1)
NPRT = 1 Print orbitals at all DRC points
0 Print orbitals at F+L (default)
1 Never print orbitals
NPUN = 2 Punch all orbitals at all DRC points
1 Punch all orbitals at F+L, and occupied
orbitals at DRC points between
0 Punch all orbitals at F+L only (default)
1 Never punch orbitals
==========================================================
==========================================================
$GLOBOP group (relevant to RUNTYP=GLOBOP)
This controls a search for the global minimum energy.
It is primarily intended for locating the best position
for effective fragment "solvent" molecules, perhaps with
an ab initio "solute" present also. There are options for
a single temperature Monte Carlo search, or a multi
temperature simulated annealing. Local minimization of
some or all of the structures selected by the Monte Carlo
is optional. The coordinates of accepted structures are
written to file IRCDATA, unless MOVIE2 is chosen. See
REFS.DOC for an overview of this RUNTYP.
A perl script "globop_extract" in the standard GAMESS
distribution may be helpful in collecting the results.
TEMPI = initial temperature used in the simulation.
(default = 20000 K)
TEMPF = final temperature. If TEMPF is not given and
NTEMPS is greater than 1, TEMPF will be
calculated based on a cooling factor of 0.95.
NTEMPS = number of temperatures used in the simulation.
If NTEMPS is not given but TEMPF is given,
NTEMP will be calculated based on a cooling
factor of 0.95. If neither NTEMP nor TEMPF is
given, the job defaults to a single temperature
Monte Carlo calculation.
NFRMOV = number of fragments to move on each step.
(default=1)
NGEOPT = number of geometries to be evaluated at each
temperature. (default = 100)
NTRAN = number of translational steps in each block.
(default=5)
NROT = number of rotational steps in each block.
(default=5)
NBLOCK = the number of blocks of steps can be set directly
with this variable, instead of being calculated
from NGEOPT, NTRAN, and NROT, according to
NBLOCK=NGEOPT/(NTRAN+NROT)
If NBLOCK is input, the number of geometries at
each temperature will be taken as
NGEOPT=NBLOCK*(NTRAN+NROT)
Each block has NTRAN translational steps followed
by NROT rotational steps.
MCMIN = flag to enable geometry optimization to minimize
the energy is carried out every NSTMIN steps.
(default=.true.)
NSTMIN = After this number of geometry steps are taken, a
local (NewtonRaphson) optimization will be
carried out. If this variable is set to 1, a
local minimization is carried out on every step,
reducing the MC space to the set of local minima.
Irrelevant if MCMIN is false. (default=10)
OPTN = if set to .TRUE., at the end of the run local
minimizations are carried out on the final
geometry and on the minimumenergy geometry.
(default=.FALSE.)
SCALE = an array of length two. The first element is the
initial maximum step size for the translational
coordinates (Angstroms). The second element is
the initial maximum stepsize for the rotational
coordinates (piradians). (defaults = 1,1)
AIMOVE = step range for moving ab initio atoms in the MC
simulation. If set to zero, the ab initio atoms
do not move in MC. The motion of ab initio atoms
is unsophisticated, as the move consists only of
shifting each Cartesian coordinate in the range
of plus AIMOVE to minus AIMOVE atomic units. Ab
initio atoms are allowed to relax during possible
geometry optimizations implied by MCMIN/NSTMIN.
(default=0.0)
ALPHA = controls the rate at which information from
successful steps is folded into the maximum step
sizes for each of the 6*(number of fragments)
coordinates. ALPHA varies between 0 and 1.
ALPHA=0 means do not change the maximum step
sizes, and ALPHA=1 throws out the old step sizes
whenever there is a successful step and uses the
successful step sizes as the new maxima. This
update scheme was used with the Parks method
where all fragments are moved on every step. It
is normally not used with the Metropolis method.
(default = 0)
DACRAT = the desired acceptance ratio, the program tries
to achieve this by adjusting the maximum step
size. (default = 0.5)
UPDFAC = the factor used to update the maximum step size
in the attempt to achive the desired acceptance
ratio (DACRAT). If the acceptance ratio at the
previous temperature was below DACRAT, the step
size is decreased by multiplying it by UPDFAC.
If the acceptance ratio was above DACRAT, the
step size is increased by dividing it by DACRAT
It should be between 0 and 1. (default = 0.95)
SEPTOL = the separation tolerence between atoms in the ab
initio piece and atoms in the fragments, as well
as between atoms in different fragments. If a
step moves atoms closer than this tolerence, the
step is rejected. (default = 1.5 Angstroms)
XMIN, XMAX, YMIN, YMAX, ZMIN, ZMAX = mimimum and maximum
values for the Cartesian coordinates of the
fragment. If the first point in a fragment steps
outside these boundaries, periodic boundary
conditions are used and the fragment reenters on
the opposite side of the box. The defaults of
10 for minima and +10 for maxima should usually
be changed.
BOLTWT = method for calculating the Boltzmann factor,
which is used as the probability of accepting a
step that increases the energy.
= STANDARD = use the standard Boltzmann factor,
exp(delta(E)/kT) (default)
= AVESTEP = scale the temperature by the average
step size, as recommended in the Parks reference
when using values of ALPHA greater than 0.
NPRT = controls the amount of output, with
= 2 reduces output below that of 1
= 1 reduces output further, needed for MCMIN=.true.
= 0 gives minimal output (default)
= 1 gives the normal GAMESS amount of output
= 2 gives maximum output
For large simulations, even IOUT=0 may produce
a log file too large to work with easily.
If geometry optimization is being done at each
Monte Carlo generated structure, you can use
the NPRT in $STATPT to further suppress output.
RANDOM = controls the choice of random number generator.
= DEBUG uses a simple random number generator with
a constant seed. Since the same sequence of
random numbers is generated during each job, it
is useful for debugging.
= RAND1 uses the simple random number generator
used in DEBUG, but with a variable seed.
= RAND3 uses a more sophisticated random number
generator described in Numerical Recipes, with a
variable seed (default).
IFXFRG = array whose length is the number of fragments.
It allows one or more fragments to be fixed
during the simulation.
=0 allows the fragment to move during the run
=1 fixes the fragment
For example, IFXFRG(3)=1 would fix the third
fragment, the default is IFXFRG(1)=0,0,0,...,0
MOVIE2 = a flag to create a series of structural data
which can be shown as a movie by the MacIntosh
program Chem3D. The coordinates of each accepted
geometry are written. The data is written to the
file IRCDATA. (default=.FALSE.)
==========================================================
==========================================================
$GRADEX group (optional, for RUNTYP=GRADEXTR)
This group controls the gradient extremal following
algorithm. The GEs leave stationary points parallel to
each of the normal modes of the hessian. Sometimes a GE
leaving a minimum will find a transition state, and thus
provides us with a way of finding that saddle point. GEs
have many unusual mathematical properties, and you should
be aware that they normally differ a great deal from IRCs.
The search will always be performed in cartesian
coordinates, but internal coordinates along the way may
be printed by the usual specification of NZVAR and $ZMAT.
METHOD = algorithm selection.
SR A predictorcorrector method due to Sun
and Ruedenberg (default).
JJH A method due to Jorgensen, Jensen and
Helgaker.
NSTEP = maximum number of predictor steps to take.
(default=50)
DPRED = the stepsize for the predictor step.
(default = 0.10)
STPT = a flag to indicate whether the initial geometry
is considered a stationary point. If .TRUE.,
the geometry will be perturbed by STSTEP along
the IFOLOW normal mode.
(default = .TRUE.)
STSTEP = the stepsize for jumping away from a stationary
point. (default = 0.01)
IFOLOW = Mode selection option. (default is 1)
If STPT=.TRUE., the intial geometry will be
perturbed by STSTEP along the IFOLOW normal mode.
Note that IFOLOW can be positive or negative,
depending on the direction the normal mode
should be followed in. The positive direction
is defined as the one where the largest component
of the Hessian eigenvector is positive.
If STPT=.FALSE. the sign of IFOLOW determines
which direction the GE is followed in. A positive
value will follow the GE in the uphill direction.
The value of IFOLOW should be set to the Hessian
mode which is parallel to the gradient to avoid
miscellaneous warning messages.
GOFRST = a flag to indicate whether the algorithm should
attempt to locate a stationary point. If .TRUE.,
a straight NR search is performed once the NR
step length drops below SNRMAX. 10 NR step are
othen allowed, a value which cannot be changed.
(default = .TRUE.)
SNRMAX = upper limit for switching to straight NR search
for stationary point location.
(default = 0.10 or DPRED, whichever is smallest)
OPTTOL = gradient convergence tolerance, in Hartree/Bohr.
Used for optimizing to a stationary point.
Convergence of a geometry search requires the
rms gradient to be less than OPTTOL.
(default=0.0001)
HESS = selection of the initial hessian matrix, if
STPT=.TRUE.
= READ causes the hessian to be read from a $HESS
group.
= CALC causes the hessian to be computed. (default)
 the next parameters apply only to METHOD=SR 
DELCOR = the corrector step should be smaller than this
value before the next predictor step is taken.
(default = 0.001)
MYSTEP = maximum number of micro iteration allowed to
bring the corrector step length below DELCOR.
(default=20)
SNUMH = stepsize used in the numerical differentiation
of the Hessian to produce third derivatives.
(default = 0.0001)
HSDFDB = flag to select determination of third derivatives.
At the current geometry we need the gradient, the
Hessian, and the partial third derivative matrix
in the gradient direction.
If .TRUE., the gradient is calculated at the
current geometry, and two Hessians are calculated
at SNUMH distance to each side in the gradient
direction. The Hessian at the geometry is formed
as the average of the two displaced Hessians.
If .FALSE., both the gradient and Hessian are
calculated at the current geometry, and one
additional Hessian is calculated at SNUMH in the
gradient direction.
The default doublesided differentiation produces
a more accurate third derivative matrix, at the
cost of an additional wave function and gradient.
(default = .TRUE.)
==========================================================
* * * * * * * * * * * * * * * * * * *
See the 'further information' section
for some help with GRADEXTR runs.
* * * * * * * * * * * * * * * * * * *
==========================================================
$SURF group (relevant for RUNTYP=SURFACE)
This group allows you to probe a potential energy
surface along a small grid of points. Note that there is
no option to vary angles, only distances. The scan can
be made for any SCFTYP, or for the MP2 or CI surface. You
may specify two rather different calculations to be done
at each point on the grid, through the RUNTYPn, SCFTYPn,
and electron correlation keywords.
* * * below, 1 and 2 refer to different calculations * * *
RUNTP1,RUNTYP2 = some RUNTYP supported in $CONTRL
First RUNTYP=RUNTP1 and then RUNTYP=RUNTP2 will be
performed, for each point on the grid. The second
run is omitted if RUNTP2 is set to NONE.
default: RUNTP1=ENERGY RUNTP2=NONE
SCFTP1,SCFTP2 = some SCFTYP supported in $CONTRL
default: SCFTYP in $CONTRL
CITYP1,CITYP2 = some CITYP supported in $CONTRL
default: CITYP in $CONTRL
MPLEV1,MPLEV2 = some MPLEVL supported in $CONTRL
default: MPLEVL in $CONTRL
CCTYP1,CCTYP2 = some CCTYP supported in $CONTRL
default: CCTYP in $CONTRL
DFTYP1,DFTYP2 = some DFTTYP supported in $DFT
default: DFTTYP in $DFT
You may need to help by giving values in $CONTRL that will
permit the program to estimate what is coming in the values
here. For example, if you want to request hessians here,
it may be good to give RUNTYP=HESSIAN in $CONTRL so that
in its earliest stages of a job, the program can initialize
for 2nd derivatives. There is less checking here than on
$CONTRL input, so don't request something impossible such
as two correlaton methods simultaneously, or analytic
hessians for MP2, or other things that are impossible.
* * * below, 1 and 2 refer to different coordinates * * *
IVEC1 = an array of two atoms, defining a coordinate from
the first atom given, to the second.
IGRP1 = an array specifying a group of atoms, which must
include the second atom given in IVEC1. The
entire group will be translated (rigidly) along
the vector IVEC1, relative to the first atom
given in IVEC1.
ORIG1 = starting value of the coordinate, which may be
positive or negative. Zero corresponds to the
distance given in $DATA.
DISP1 = step size for the coordinate. If DISP1 is set
to zero, then the keyword GRID1 is read.
NDISP1 = number of steps to take for this coordinate.
GRID1 = an array of grid points at which to compute the
energy. This option is an alternative to the
ORIG1, DISP1 input which produces an equidistant
grid. To use GRID1, one has to set DISP1=0.0.
The number of grid points is given in NDISP1, and
is limite to at most 100 grid points. The input
of GRID1(1)=ORIG1,ORIG1+DISP1,ORIG1+DISP1*2,...
would reproduce an equidistant grid given by ORIG1
and DISP1.
ORIG1, DISP1, and GRID1 should be given in Angstrom.
There are no reasonable defaults for these keywords.
IVEC2, IGRP2, ORIG2, DISP2, NDISP2, GRID2 have the same
meaning as their "1" counterparts, and permit you to make
a two dimensional map along two displacement coordinates.
If the "2" data are not input, the surface map proceeds in
only one dimension.
==========================================================
==========================================================
$LOCAL group (relevant if LOCAL=RUEDNBRG, BOYS, or POP)
This group allows input of additional data to control
the localization methods. If no input is provided, the
valence orbitals will be localized as much as possible,
while still leaving the wavefunction invariant. There are
many specialized options for Localized Charge Distribution
analysis, and for EFP generation.
N.B. Since Boys localization needs the dipole integrals,
do not turn off dipole moment calculation in $ELMOM.
MAXLOC = maximum number of localization cycles. This
applies to BOYS or POP methods only. If the
localization fails to converge, a different
order of 2x2 pairwise rotations will be tried.
(default=250)
CVGLOC = convergence criterion. The default provides
LMO coefficients accurate to 6 figures.
(default=1.0E6)
SYMLOC = a flag to restrict localization so that orbitals
of different symmetry types are not mixed. This
option is not supported in all possible point
groups. The purpose of this option is to give a
better choice for the starting orbitals for GVBPP
or MCSCF runs, without destroying the orbital's
symmetry. This option is compatible with each of
the 3 methods of selecting the orbitals to be
included. (default=.FALSE.)
ORIENT = a flag to request orientation of the localized
orbitals for bondorder analysis. After the
localization, the orbitals on each atom are
rotated only among themselves, in order to direct
the orbitals towards neighboring atom's orbitals,
to which they are bonded. The density matrix,
or bondorder matrix, of these Oriented LMOs is
readily interpreted as atomic populations and
bond orders. This option can be used only for
SCFTYP=MCSCF and LOCAL=RUEDENBRG.
(default=.FALSE.)
PRTLOC = a flag to control supplemental printout. The
extra output is the rotation matrix to the
localized orbitals, and, for the Boys method,
the orbital centroids, for the Ruedenberg
method, the coulomb and exchange matrices,
for the population method, atomic populations.
(default=.FALSE.)
 The following keywords select the orbitals which
are to be included in the localization. You may
select from FCORE, NOUTA/NOUTB, or NINA/NINB,
but may choose only one of these three groups.
FCORE = flag to freeze all the chemical core orbitals
present. All the valence orbitals will be
localized. You must explicitly turn this
option off to choose one of the other two
orbital selection options. (default=.TRUE.)
* * *
NOUTA = number of alpha orbitals to hold fixed in the
localization. (default=0)
MOOUTA = an array of NOUTA elements giving the numbers of
the orbitals to hold fixed. For example, the
input NOUTA=2 MOOUTA(1)=8,13 will freeze only
orbitals 8 and 13. You must enter all the
orbitals you want to freeze, including any cores.
This variable has nothing to do with cows.
NOUTB = number of beta orbitals to hold fixed in UHF
localizations. (default=0)
MOOUTB = same as MOOUTA, except that it applies to the
beta orbitals, in UHF wavefunctions only.
* * *
NINA = number of alpha orbitals which are to be
included in the localization. (default=0)
MOINA = an array of NINA elements giving the numbers of
the orbitals to be included in the localization.
Any orbitals not mentioned will be frozen.
NINB = number of UHF beta MOs in the localization.
(default=0)
MOINB = same as MOINA, except that it applies to the
beta orbitals, in UHF wavefunctions only.
ORMFUL = this flag is relevant only to CISTEP=ORMAS MCSCF
localizations. By default, the localization is
restricted such that the multiple active spaces
are not mixed, leaving the total wavefunction
invariant. It may be used to localize within the
full range of active MOs. (Default is .FALSE.)
 The following keywords are used for the localized
charge distribution (LCD) energy decomposition.
EDCOMP = flag to turn on LCD energy decomposition.
Note that this method is currently implemented
for SCFTYP=RHF and ROHF and LOCAL=RUEDNBRG only.
The SCF LCD forces all orbitals to be localized,
overriding input on the previous page. See also
LMOMP2 in the $MP2 group. (default = .FALSE.)
$LOCAL
MOIDON = flag to turn on LMO identification and subsequent
LMO reordering, and assign nuclear LCD automat
ically. (default = .FALSE.)
DIPDCM = flag for LCD molecular dipole decomposition.
(default = .FALSE.)
QADDCM = flag for LCD molecular quadrupole decomposition.
(default = .FALSE.)
POLDCM = flag to turn on LCD polarizability decomposition.
This method is implemented for SCFTYP=RHF or ROHF
and LOCAL=BOYS or RUEDNBRG. (default=.FALSE.,
except that RUNTYP=MAKEFP turns this computation
on, automatically. LMO dipole polarizabilities
are the polarizability term in the EFP model)
POLNUM = flag to forces numerical rather than analytical
calculation of the polarizabilities. This may be
useful in larger molecules. The numerical
polarizabilities of bonds in or around aromatic
rings sometimes are unphysical. (default=.FALSE.)
See D.R.Garmer, W.J.Stevens
J.Phys.Chem. 93, 82638270(1989).
POLAPP = flag to force calculation of the polarizabilities
using a perturbation theory expression. This may
be useful in larger molecules. (default=.FALSE.)
See R.M. Minikis, V. Kairys, J.H. Jensen
J.Phys.Chem.A 105, 38293837(2001)
POLANG = flag to choose units of localized polarizability
output. The default is Angstroms**3, while false
will give Bohr**3. (default=.TRUE.)
ZDO = flag for LCD analysis of a composite wavefunction,
given in a $VEC group of a van der Waals complex,
using the zero differential overlap approximation.
The MOs are not orthonormalized and the inter
molecular electron exchange energy is neglected.
Also, the molecular overlap matrix is printed
out. This is a very specialized option.
(default = .FALSE.)
 The following keywords can be used to define the
nuclear part of an LCD. They are usually used to
rectify mistakes in the automatic definition
made when MOIDON=.TRUE. The index defining the
LMO number then refers to the reordered list of LMOs.
NMOIJ = array giving the number of nuclei assigned to a
particular LMO.
IJMO = is an array of pairs of indices (I,J), giving
the row (nucleus I) and column (orbital J)
index of the entries in ZIJ and MOIJ.
MOIJ = arrays of integers K, assigning nucleus K as the
site of the Ith charge of LCD J.
ZIJ = array of floating point numbers assigning a
charge to the Ith charge of LCD J.
IPROT = array of integers K, defining nucleus K as a
proton.
DEPRNT = a flag for additional decomposition printing,
such as pair contributions to various energy
terms, and centroids of the Ruedenberg orbitals.
(default = .FALSE.)
 The following keywords are used to build large EFPs
from several RUNTYP=MAKEFP runs on smaller molecular
fragments, by excluding common regions of overlap.
For example, an EFP for noctanol can be build from
two MAKEFP runs, on npentane and npentanol,
CH3CH2CH2CH2CH2CH2CH2CH2OH
CH3CH2CH2CH2[CH3]
[CH3]CH2CH2CH2CH2OH
by excluding operlapping regions shown in brackets
from the two EFPs. See J.Phys.Chem.A 105, 38293837,
(2001) for more information.
NOPATM = array of atoms that define an area to be excluded
from a DMA ($STONE) during a RUNTYP=MAKEFP run.
All atomic centers specified, and the midpoints
of any bonds to them, are excluded as expansion
points. The density due to all LMOs primarily
centered on these atoms are excluded from the DMA
(see also KMIDPT). Furthermore, polarizability
tensors for these LMOs are excluded.
KPOINT = array of "boundary atoms", those atoms that are
covalently bonded to the atoms given in NOATM.
KMIDPT = flag to indicate whether the density due to bond
LMOs (and associated expansion points) between
the NOPATM atoms and the KPOINT atoms are to be
included in the DMA. (default = .TRUE.)
NODENS = an array that specifies the atoms for which the
associated electronic density will be removed
before the multipole expansion. This provides an
EFP with net integer charge. (P.A.Molina, H.Li,
J.H.Jensen J.Comput.Chem. 24, 19721979(2003).
The following keywords relate to the computation of
imaginary frequency dynamic polarizabilities. This is
useful in the development of the dispersion energy formula
in the EFP2 model, but may also be computed separately, if
wished.
POLDYN = a flag to compute imaginary frequency dynamic
polarizabilities. (default=.FALSE., but .TRUE. if
RUNTYP=MAKEFP)
NDPFRQ = number of imaginary frequencies to compute.
Default=1 for most runs, but=12 if RUNTYP=MAKEFP.
DPFREQ = an array of imaginary frequencies to be used,
entered as real numbers (absolute values). The
default=0.0 for most runs, which is silly, because
this just computes the normal static dipole
polarizability! For RUNTYP=MAKEFP, the program
uses 12 internally stored values, which serve as
the roots for a GaussLegendre quadrature to
extract the C6 dispersion coefficients. Given in
atomic units.
For more information, see
I.Adamovic, M.S.Gordon Mol.Phys. 103, 379387(2005).
==========================================================
* * * * * * * * * * * * * * * * * *
For hints about localizations, and
the LCD energy decomposition, see
the 'further information' section.
* * * * * * * * * * * * * * * * * *
==========================================================
$TWOEI group (relevant for EDCOMP=.TRUE. in $LOCAL)
Formatted transformed twoelectron Coulomb and Exchange
integrals as punched during a LOCAL=RUEDNBRG run. If this
group is present it will automaticall be read in during
such a run and the twoelectron integrals do not have to
be retransformed. This group is especially useful for
EDCOMP=.TRUE. runs when the localization has to be repeated
for different definitions of nuclear LCDs.
==========================================================
==========================================================
$TRUNCN group (optional, relevant for RHF)
This group controls the truncation of some of the
localized orbitals to just the AOs on a subset of the
atoms. This option is particularly useful to generate
localized orbitals to be frozen when the effective
fragment potential is used to partition a system across a
chemical bond. In other words, this group prepares the
frozen buffer zone orbitals. This group should be used in
conjunction with RUNTYP=ENERGY (or PROP if the orbitals
are available) and either LOCAL=RUEDNBRG or BOYS, with
MOIDON set in $LOCAL.
DOPROJ = flag to activate MO projection/truncation, the
default is to skip this (default=.FALSE.)
AUTOID = forces identification of MOs (analogous to MOIDON
in $LOCAL). This keyword is provided in case the
localized orbitals are already present in $VEC,
in which case this is a faster RUNTYP=PROP with
LOCAL=NONE job. Obviously, GUESS=MOREAD.
(default=.FALSE.)
PLAIN = flag to control the MO tail truncation. A value
of .FALSE. uses corresponding orbital projections,
H.F.King, R.E.Stanton, H.Kim, R.E.Wyatt, R.G.Parr
J. Chem. Phys. 47, 19361941(1967) and generates
orthogonal orbitals. A value of .TRUE. just sets
the unwanted AOs to zero, so the resulting MOs
need to go through the automatic orthogonalization
step when MOREAD in the next job.
(default=.FALSE.)
IMOPR = an array specifying which MOs to be truncated. In
most cases involving normal bonding, the options
MOIDON or AUTOID will correctly identify all
localized MOs belonging to the atoms in the zone
being truncated. However, you can inspect the
output, and give a list of all MOs which you want
to be truncated in this array, in case you feel
the automatic assignment is incorrect.
Any orbital not in the truncation set, whether
this is chosen automatically or by IMOPR, is left
completely unaltered.
  
There are now two ways to specify what orbitals are to
be truncated. The most common usage is for preparation of
a buffer zone for QM/MM computations, with an Effective
Fragment Potential representing the nonquantum part of
the system. This input is NATAB, NATBF, ICAPFR, ICAPBF,
in which case the $DATA input must be sorted into three
zones. The first group of atoms are meant to be treated
in later runs by full quantum mechanics, the second
group by frozen localized orbitals as a 'buffer', and the
third group is to be substituted later by an effective
fragment potential (multipoles, polarizabilities, ...).
Note that in the DOPROJ=.TRUE. run, all atoms are still
quantum atoms.
NATAB = number of atoms to be in the 'ab initio' zone.
NATBF = number of atoms to be in the 'buffer' zone.
The program can obtain the number of atoms in
the remaining zone by subtraction, so it need
not be input.
In case the MOIDON or AUTOID options lead to confused
assignments (unlikely in ordinary bonding situations
around the buffer zone), there are two fine tuning values.
ICAPFR = array indicating the identity of "capping atoms"
which are on the border between the ab initio and
buffer zones (in the ab initio zone).
ICAPBK = array indicating the identity of "capping atoms"
which are on the border between the buffer and EFP
zones (in the effective fragment zone).
See also IXCORL and IXLONE below.
  
In case truncation seems useful for some other purpose,
you can specify the atoms in any order within the $DATA
group, by the IZAT/ILAT approach. You are supposed to
give only one of these two lists, probably whichever is
shorter:
IZAT = an array containing the atoms which are NOT in
the buffer zone.
ILAT = an array containing the atoms which are in
the buffer zone.
The AO coefficients of the localized orbitals present in
the buffer zone which lie on atoms outside the buffer will
be truncated.
See also IXCORL and IXLONE below.
  
The next two values let you remove additional orbitals
within the buffer zone from the truncation process, if that
is desirable. These arrays can only include atoms that are
already in the buffer zone, whether this was defined by
NATBF, or IZAT/ILAT. The default is to include all core
and lone pair orbitals, not just bonding orbitals, as the
buffer zone orbitals.
IXCORL = an array of atoms whose core and lone pair
orbitals are to be considered as not belonging
to the buffer zone orbitals.
IXLONE = an array of atoms for which only the lone pair
orbitals are to be considered as not belonging
to the buffer zone orbitals.
The final option controls output of the truncated orbitals
to file PUNCH for use in later runs:
NPUNOP = punch out option for the truncated orbitals
= 1 the MOs are not reordered.
= 2 punch the truncated MOs as the first vectors
in the $VEC MO set, with untransformed vectors
following immediately after. (default)
==========================================================
==========================================================
$ELMOM group (not required)
This group controls electrostatic moments calculation.
The symmetry properties of multipoles are discussed in
A.Gelessus, W.Thiel, W.Weber
J.Chem.Ed. 72, 505508(1995)
IEMOM = 0  skip this property
1  calculate monopole and dipole (default)
2  also calculate quadrupole moments
3  also calculate octopole moments
WHERE = COMASS  center of mass (default)
NUCLEI  at each nucleus
POINTS  at points given in $POINTS.
OUTPUT = PUNCH, PAPER, or BOTH (default)
IEMINT = 0  skip printing of integrals (default)
1  print dipole integrals
2  also print quadrupole integrals
3  also print octopole integrals
2  print quadrupole integrals only
3  print octopole integrals only
The quadrupole and octopole tensors on the printout
are formed according to the definition of Buckingham.
Caution: only the first nonvanishing term in the multi
ipole charge expansion is independent of the coordinate
origin chosen, which is normally the center of mass.
==========================================================
==========================================================
$ELPOT group (not required)
This group controls electrostatic potential calculation.
IEPOT = 0 skip this property (default)
1 calculate electric potential
WHERE = COMASS  center of mass
NUCLEI  at each nucleus (default)
POINTS  at points given in $POINTS
GRID  at grid given in $GRID
PDC  at points controlled by $PDC.
OUTPUT = PUNCH, PAPER, or BOTH (default)
This property is the electrostatic potential V(a) felt
by a test positive charge, due to the molecular charge
density. A nucleus at the evaluation point is ignored.
If this property is evaluated at the nuclei, it obeys the
equation
sum on nuclei(a) Z(a)*V(a) = 2*V(nn) + V(ne).
The electronic portion of this property is called the
diamagnetic shielding.
==========================================================
==========================================================
$ELDENS group (not required)
This group controls electron density calculation.
IEDEN = 0 skip this property (default)
= 1 compute the electron density.
MORB = The molecular orbital whose electron density is
to be computed. If zero, the total density is
computed. (default=0)
WHERE = COMASS  center of mass
NUCLEI  at each nucleus (default)
POINTS  at points given in $POINTS
GRID  at grid given in $GRID
OUTPUT = PUNCH, PAPER, or BOTH (default)
IEDINT = 0  skip printing of integrals (default)
1  print the electron density integrals
==========================================================
==========================================================
$ELFLDG group (not required)
This group controls electrostatic field and electric
field gradient calculation.
IEFLD = 0  skip this property (default)
1  calculate field
2  calculate field and gradient
WHERE = COMASS  center of mass
NUCLEI  at each nucleus (default)
POINTS  at points given in $POINTS
OUTPUT = PUNCH, PAPER, or BOTH (default)
IEFINT = 0  skip printing these integrals (default)
1  print electric field integrals
2  also print field gradient integrals
2  print field gradient integrals only
The HellmanFeynman force on a nucleus is the nuclear
charge multiplied by the electric field at that nucleus.
The electric field is the gradient of the electric
potential, and the field gradient is the hessian of the
electric potential. The components of the electric field
gradient tensor are formed in the conventional way, i.e.
see D.Neumann and J.W.Moskowitz.
==========================================================
==========================================================
$POINTS group (not required)
This group is used to input points at which properties
will be computed. This first card in the group must
contain the string ANGS or BOHR, followed by an integer
NPOINT, the number of points to be used. The next NPOINT
cards are read in free format, containing the X, Y, and Z
coordinates of each desired point.
==========================================================
$GRID group (not required)
This group is used to input a grid (plane through the
molecule) on which properties will be calculated.
ORIGIN(i) = coordinates of the lower left corner of
the plot.
XVEC(i) = coordinates of the lower right corner of
the plot.
YVEC(i) = coordinates of the upper left corner of
the plot.
SIZE = grid increment, default is 0.25.
UNITS = units of the above four values, it can be
either BOHR or ANGS (the default).
Note that XVEC and YVEC are not necessarily parallel to
the X and Y axes, rather they are the axes which you
desire to see plotted by the MEPMAP contouring program.
==========================================================
* * * * * * * * * * * * * * * * * * * *
For conversion factors, and references
see the 'further information' section.
* * * * * * * * * * * * * * * * * * * *
==========================================================
$PDC group (relevant if WHERE=PDC in $ELPOT)
This group determines the points at which to compute
the electrostatic potential, for the purpose of fitting
atomic charges to this potential. Constraints on the fit
which determines these "potential determined charges" can
include the conservation of charge, the dipole, and the
quadrupole.
PTSEL = determines the points to be used, choose
GEODESIC to use a set of points on several fused
sphere van der Waals surfaces, with points
selected using an algorithm due to Mark
Spackman. The results are similar to those
from the Kollman/Singh method, but are
less rotation dependent. (default)
CONNOLLY to use a set of points on several fused
sphere van der Waals surfaces, with points
selected using an algorithm due to Michael
Connolly. This is identical to the method
used by Kollman & Singh (see below)
CHELPG to use a modified version of the CHELPG
algorithm, which produces a symmetric
grid of points for a symmetric molecule.
CONSTR = NONE  no fit is performed. The potential at
the points is instead output according
to OUTPUT in $ELPOT.
CHARGE  the sum of fitted atomic charges is
constrained to reproduce the total
molecular charge. (default)
DIPOLE  fitted charges are constrained to
exactly reproduce the total charge
and dipole.
QUPOLE  fitted charges are constrained to
exactly reproduce the charge, dipole,
and quadrupole.
Note: the number of constraints cannot exceed
the number of parameters, which is the number
of nuclei. Planar molecules afford fewer
constraint equations, namedly two dipole
constraints and three quadrupole constraints,
instead of three and five, repectively.
* * the next 5 pertain to PTSEL=GEODESIC or CONNOLLY * *
VDWSCL = scale factor for the first shell of VDW spheres.
The default of 1.4 seems to be an empirical best
value. Values for VDW radii for most elements up
to Z=36 are internally stored.
VDWINC = increment for successive shells (default = 0.2).
The defaults for VDWSCL and VDWINC will result
in points chosen on layers at 1.4, 1.6, 1.8 etc
times the VDW radii of the atoms.
LAYER = number of layers of points chosen on successive
fused sphere VDW surfaces (default = 4)
NFREQ = flag for particular geodesic tesselation of
points. Only relevant if PTSEL=GEODESIC.
Options are:
(10*h + k) for {3,5+}h,k tesselations
(10*h + k) for {5+,3}h,k tesselations
Of course both nh and nk must be less than 10,
so NFREQ must lie within the range 99 to 99.
The default value is NFREQ=30 (=03)
PTDENS = density of points on the surface of each scaled
VDW sphere (in points per square au). Relevant
if PTSEL=CONNOLLY. Default=0.28 per au squared,
which corresponds to 1.0 per square Angstrom, the
default recommended by Kollman & Singh.
* * * the next two pertain to PTSEL=CHELPG * * *
RMAX = maximum distance from any point to the closest
atom. (default=3.0 Angstroms)
DELR = distance between points on the grid.
(default=0.8 Angstroms)
MAXPDC = an estimate of the total number of points whose
electrostatic potential will be included in the
fit. (default=10000)
CENTER = an array of coordinates at which the moments were
computed.
DPOLE = the molecular dipole.
QPOLE = the molecular quadrupole.
PDUNIT = units for the above values. ANGS (default) will
mean that the coordinates are in Angstroms, the
dipole in Debye, and quadrupole in Buckinghams.
BOHR implies atomic units for all 3.
Note: it is easier to compute the moments in the
current run, by setting IEMOM to at least 2 in
$ELMOM. However, you could fit experimental data,
for example, by reading it in here.
==========================================================
There is no unique way to define fitted atomic
charges. Smaller numbers of points at which the electro
static potential is fit, changes in VDW radii, asymmetric
point location, etc. all affect the results. A useful
bibliography is
U.C.Singh, P.A.Kollman, J.Comput.Chem. 5, 129145(1984)
L.E.Chirlain, M.M.Francl, J.Comput.Chem. 8, 894905(1987)
R.J.Woods, M.Khalil, W.Pell, S.H.Moffatt, V.H.Smith,
J.Comput.Chem. 11, 297310(1990)
C.M.Breneman, K.B.Wiberg, J.Comput.Chem. 11, 361373(1990)
K.M.Merz, J.Comput.Chem. 13, 749(1992)
M.A.Spackman, J.Comput.Chem. 17, 118(1996)
Start your reading with the last paper shown.
==========================================================
$MOLGRF group (relevant only if you have MOLGRAPH)
This option provides an interface for viewing orbitals
through a commercial package named MOLGRAPH, from Daikin
Industries. Note that this option uses three disk files
which are not defined in the GAMESS execution scripts we
provide, since we don't use MOLGRAPH ourselves. You will
need to define files 28, 29, 30, as generic names PRGRID,
COGRID, MOGRID, of which the latter is passed to MOLGRAPH.
GRID3D = a flag to generate 3D grid data.
(default is .false.).
TOTAL = a flag to generate a total density grid data.
"Total" means the sum of the orbital densities
given by NPLT array. (default is .false.).
MESH = numbers of grids. You can use different numbers
for three axes. (default is MESH(1)=21,21,21).
BOUND = boundary coordinates of a 3D graphical cell. The
default is that the cell is larger than the
molecular skeleton by 3 bohr in all directions.
E.g., BOUND(1)=xmin,xmax,ymin,ymax,zmin,zmax
NPLOTS = number of orbitals to be used to generate 3D grid
data. (default is NPLOTS=1).
NPLT = orbital IDs. The default is 1 orbital only, the
HOMO or SOMO. If the LOCAL option is given in
$CONTRL, localized orbital IDs should be given.
For example, NPLT(1)=n1,n2,n3,...
CHECK = debug option, printing some of the grid data.
If you are interested in graphics, look at the WWW page
for information about other graphics packages with GAMESS.
In particular, if you have a MacIntosh, look at the
MacMolPlt program available at our web site.
==========================================================
==========================================================
$STONE group (optional)
This group defines the expansion points for Stone's
distributed multipole analysis (DMA) of the electrostatic
potential.
The DMA takes the multipolar expansion of each overlap
charge density defined by two gaussian primitives, and
translates it from the center of charge of the overlap
density to the nearest expansion point. Some references
for the method are
A.J.Stone Chem.Phys.Lett. 83, 233239 (1981)
A.J.Stone M.Alderton Mol.Phys. 56, 10471064(1985)
The existence of a $STONE group in the input is what
triggers the analysis. Enter as many lines as you wish,
in any order, terminated by a $END record.

ATOM i name, where
ATOM is a keyword indicating that a particular
atom is selected as an expansion center.
i is the number of the atom
name is an optional name for the atom. If not
entered the name will be set to the name
used in the $DATA input.

ATOMS is a keyword selecting all nuclei in the
molecule as expansion points. No other
input on the line is necessary.

BONDS is a keyword selecting all bond midpoints
in the molecule as expansion points. No
other input on the line is necessary.

BOND i j name, where
BOND is a keyword indicating that a bond mid
point is selected as an expansion center.
i,j are the indices of the atoms defining the
bond, corresponding to two atoms in $DATA.
name an optional name for the bond midpoint.
If omitted, it is set to 'BOND'.

CMASS is a keyword selecting the center of mass
as an expansion point. No other input on
the line is necessary.

POINT x y z name, where
POINT is a keyword indicating that an arbitrary
point is selected as an expansion point.
x,y,z are the coordinates of the point, in Bohr.
name is an optional name for the expansion
point. If omitted, it is set to 'POINT'.

While making the EFPs for QM/MM run, a single keyword
QMMMBUF is necessary. Adding additional keywords may lead
to meaningless results. The program will automatically
select atoms and bond midpoints which are outside the
buffer zone as the multipole expansion points.
QMMMBUF nmo, where
QMMMBUF is a keyword specifying the number of QM/MM
buffer molecular orbitals, which must be the
first NMO orbitals in the MO set. These
orbitals must be frozen in the buffer zone,
so this is useful only if $MOFRZ is given.
NMO is the number of buffer MOs
(if NMO is omitted, it will be set to the
number of frozen MOs in $MOFRZ)
==========================================================
The second and third moments on the printout can be
converted to Buckingham's tensors by formula 9 of
A.D.Buckingham, Quart.Rev. 13, 183214 (1959)
These can in turn be converted to spherical tensors
by the formulae in the appendix of
S.L.Price, et al. Mol.Phys. 52, 9871001 (1984)
==========================================================
$RAMAN group (relevant for all SCFTYPs)
This input controls the computation of Raman intensity
by the numerical differentiation produre of Komornicki and
others. It is applicable to any wavefunction for which
the analytic gradient is available, including some MP2 and
CI cases. The calculation involves the computation of 19
nuclear gradients, one without applied electric fields,
plus 18 no symmetry runs with electric fields applied in
various directions. The numerical second differencing
produces intensity values with 23 digits of accuracy.
This run must follow an earlier RUNTYP=HESSIAN job,
and the $GRAD and $HESS groups from that first job must be
given as input. If the $DIPDR is computed analytically
by this Hessian job, it too may be read in, if not, the
numerical Raman job will evaluate $DIPDR. Once the data
from the 19 applied fields is available, the $ALPDR tensor
is evaluated. Then the nuclear derivatives of the dipole
moment and alpha polarizability will be combined with the
normal coordinate information to produce the IR and Raman
intensity of each mode.
To study isotopic substitution speedily, input the
$GRAD, $HESS, $DIPDR, and $ALPDR groups along with the
desired atomic masses in $MASS.
The code does not permit semiempirical or solvation
models to be used.
EFIELD = applied electric field strenth. The literature
suggests values in the range 0.001 to 0.005.
(default = 0.002 a.u.)
==========================================================
==========================================================
$ALPDR group (relevant for RUNTYP=RAMAN or HESSIAN)
Formatted alpha derivative tensor, punched by a previous
RUNTYP=RAMAN job. If both $DIPDR and this group are found
in the input file, the applied field computation will be
skipped, to immediately evaluate IR and Raman intensities.
If this group is found during RUNTYP=HESSIAN, the Raman
intensities will be added to the output. You might want
to run as RUNTYP=HESSIAN instead of RUNTYP=RAMAN in order
to have access to PROJCT or the other options available in
the $FORCE group.
==========================================================
==========================================================
$NMR group (optional, relevant if RUNTYP=NMR)
This group governs the analytic computation of the NMR
shielding tensor for each nucleus, using the Gauge
Invariant Atomic Orbital (GIAO) method, also known as
London orbitals. The most useful input values are the
first three printing options. The wavefunction must be
RHF, the atomic basis set may be spdfg, the EFP model may
be used to include solvent effects, and the McMurchie
Davidson integrals used are not fast.
ANGINT = a flag to control the evaluation of the perturbed
twoelectron integrals by increasing the angular
momentum on the unperturbed 2e integrals. With
this selected, only two passes through the 2e
NMR integral code are needed. Otherwise, six
slow passes are needed, and option meant only
for debugging purposes. (default=.TRUE.)
INMEM A flag to carry all integrals in memory. If
selected, the calculation will require several
multiples of NAO**4. By default, the calculation
will require space on the order of NATOMS*NAO**2,
where NAO is the basis set dimension. This is
useful for debugging. (default=.FALSE.)
The rest are print flags, in increasing order of the amount
of output created, as well as decreasing order of interest.
The default for all of these options is .FALSE.
PDIA Print diamagnetic term of the shielding tensor.
PPARA Print paramagnetic term of the shielding tensor.
PEVEC Print eigenvectors of asymmetric shielding tensor.
PITER Print iteration data for the formation of the
three firstorder density matrices.
PRMAT Print the three firstorder perturbed density
matrices, the three firstorder H matrices for
each nucleus, the unperturbed density matrix, and
the nine secondorder H matrices for each nucleus.
POEINT Print all oneelectron integrals.
PTEINT Print the perturbed twoelectron integrals.
TEDBG Print VAST amounts of debugging information for
the McMurchieDavidson twoelectron intgrals.
Should only be used for the smallest test jobs.
==========================================================
==========================================================
$MOROKM group (relevant if RUNTYP=MOROKUMA)
This group controls how the supermolecule input in the
$DATA group is divided into two or more monomers. Both
the supermolecule and its constituent monomers must be well
described as closed shells by RHF wavefunctions.
MOROKM = a flag to request MorokumaKitaura decomposition.
(default is .TRUE.)
RVS = a flag to request "reduced variation space"
decomposition. This differs from the Morokuma
option, and one or the other or both may be
requested in the same run. (default is .FALSE.)
BSSE = a flag to request basis set superposition error
be computed. You must ensure that CTPSPL is
selected. This option applies only to MOROKM
decompositions, as a basis superposition error is
automatically generated by the RVS scheme. This
is not the full Boys counterpoise correction, as
explained in the reference. (default is .FALSE.)
* * *
IATM = An array giving the number of atoms in each of
the monomer. Up to ten monomers may be defined.
Your input in $DATA must have all the atoms in
the first monomer defined before the atoms in the
second monomer, before the third monomer... The
number of atoms belonging to the final monomer
can be omitted. There is no sensible default for
IATM, so don't omit it from your input.
ICHM = An array giving the charges of the each monomer.
The charge of the final monomer may be omitted,
as it is fixed by ICH in $CONTRL, which is the
total charge of the supermolecule. The default
is neutral monomers, ICHM(1)=0,0,0,...
EQUM = a flag to indicate all monomers are equivalent
by symmetry (in addition to containing identical
atoms). If so, which is not often true, then only
the unique computations will be done.
(default is .FALSE.)
CTPSPL = a flag to decompose the interaction energy into
charge transfer plus polarization terms. This
is most appropriate for weakly interacting
monomers. (default is .TRUE.)
CTPLX = a flag to combine the CT and POL terms into a
single term. If you select this, you might want
to turn CTPSPL off to avoid the extra work that
that decomposition entails, or you can analyze
both ways in the same run (default=.FALSE.)
RDENG = a flag to enable restarting, by reading the
lines containing "FINAL ENERGY" from a previous
run. The $ENERGY group is single lines read
under format A16,F20.10 containing the E, and a
card $END to complete. The 16 chars = anything.
(default is .FALSE.)
==========================================================
The present implementation has some quirks:
1. The initial guess of the monomer orbitals is not
controlled by $GUESS. The program first looks for a
$VEC1, $VEC2, ... group for each monomer. The orbitals
must be obtained for coordinates that the monomer has
within the supermolecule. If any $VECn groups are
found, they will be MOREAD. If any are missing, the
guess for that monomer will be constructed by HCORE.
Check your monomer energies carefully! The initial
guess orbitals for the supermolecule are formed from a
block diagonal matrix made from the monomer orbitals.
2. The use of symmetry is turned off internally.
3. Spherical harmonics may not be used.
4. There is no direct SCF option. File ORDINT will be a
full C1 list of integrals. File AOINTS will contain
whatever subset of these is needed for each particular
decomposition step. So extra disk space is needed
compared to RUNTYP=ENERGY.
5. This run type applies only to ab initio RHF treatment
of the monomers. To be quite specific: this means
that MOPAC's approximated 2e integrals will not work,
nor will DFT (part of whose Fock interactions come from
numerical integration of grid points, rather than 2e
integrals).
6. This kind of run will work correctly in parallel.
References:
C.Coulson in "Hydrogen Bonding", D.Hadzi, H.W.Thompson,
Eds., Pergamon Press, NY, 1957, pp 339360.
C.Coulson Research, 10, 149159 (1957).
K.Morokuma J.Chem.Phys. 55, 123644 (1971).
K.Kitaura, K.Morokuma Int.J.Quantum Chem. 10, 325 (1976).
K.Morokuma, K.Kitaura in "Chemical Applications of
Electrostatic Potentials", P.Politzer,D.G.Truhlar, Eds.
Plenum Press, NY, 1981, pp 215242.
The method coded is the newer version described in the 1976
and 1981 papers. In particular, note that the CT term is
computed separately for each monomer, as described in the
words below eqn. 16 of the 1981 paper, not simultaneously.
Reduced Variational Space:
W.J.Stevens, W.H.Fink, Chem.Phys.Lett. 139, 1522(1987).
A comparison of the RVS and Morokuma decompositions can
be found in the review article: "Wavefunctions and
Chemical Bonding" M.S.Gordon, J.H.Jensen in "Encyclopedia
of Computational Chemistry", volume 5, P.V.R.Schleyer,
editor, John Wiley and Sons, Chichester, 1998.
BSSE during Morokuma decomposition:
R.Cammi, R.Bonaccorsi, J.Tomasi
Theoret.Chim.Acta 68, 271283(1985).
The present implementation:
"Energy decomposition analysis for manybody interactions,
and application to water complexes"
W.Chen, M.S.Gordon J.Phys.Chem. 100, 1431614328(1996)
==========================================================
$FFCALC group (relevant for RUNTYP=FFIELD)
This group permits the study of the influence of an
applied electric field on the wavefunction. The most
common finite field calculation applies a sequence of
fields to extract the linear polarizability and first and
second order hyperpolarizability. The method is general,
and so works for all ab initio wavefunctions in GAMESS.
EFIELD = applied electric field strength
(default=0.001 a.u.)
IAXIS and JAXIS specify the orientation of the applied
field. 1,2,3 mean x,y,z respectively.
The default is IAXIS=3 and JAXIS=0.
If IAXIS=i and JAXIS=0, the program computes alpha(ii),
beta(iii), and gamma(iiii) from the energy changes, and
a few more components from the dipole changes. Five
wavefunction evaluations are performed.
If IAXIS=i and JAXIS=j, the program computes the cross
terms beta(ijj), beta(iij), and gamma(iijj) from the
energy changes, and a few more components from dipole
changes. This requires nine wavefunction evaluations.
AOFF = a flag to permit evaluation of alpha(ij)
when the dipole moment is not available.
This is necessary only for MP2, and means
the offaxial calculation will do 13, not
9 energy evaluations. Default=.FALSE.
SYM = a flag to specify when the fields to be
applied along the IAXIS and/or JAXIS (or
according to EONE below) do not break the
molecular symmetry. Since most fields do
break symmetry, the default is .FALSE.
ONEFLD = a flag to specify a single applied field
calculation will be performed. Only the
energy and dipole moment under this field
are computed. If this option is selected,
only SYM and EONE input is heeded. The
default is .FALSE.
EONE = an array of the three x,y,z components of
the single applied field.
Finite field calculations require large basis sets,
and extraordinary accuracy in the wavefunction. To
converge the SCF to many digits is sometimes problematic,
but we suggest you use the input to increase integral
accuracy and wavefunction convergence, for example
$CONTRL ICUT=20 ITOL=30 $END
$SCF CONV=1.0d10 FDIFF=.FALSE. $END
In many cases, the applied fields will destroy the
molecular symmetry. This means the integrals are
calculated once with point group symmetry to do the
initial field free wavefunction evaluation, and then again
with point group symmetry turned off. If the fields
applied do not destroy symmetry, you can avoid this second
calculation of the integrals by SYM=.TRUE. This option
also permits use of symmetry during the applied field
wavefunction evaluations.
Examples of fields that do not break symmetry are a
Zaxis field for an axial point group which is not
centrosymmetric (i.e. C2v). However, a second field in
the X or Y direction does break the C2v symmetry.
Application of a Zaxis field for benzene breaks D6h
symmetry. However, you could enter the group as C6v in
$DATA while using D6h coordinates, and regain the prospect
of using SYM=.TRUE. If you wanted to go on to apply a
second field for benzene in the X direction, you might
want to enter Cs in $DATA, which will necessitate the
input of two more carbon and hydrogen atom, but recovers
use of SYM=.TRUE.
Reference: H.A.Kurtz, J.J.P.Stewart, K.M.Dieter
J.Comput.Chem. 11, 8287 (1990).
For analytic computation of static and also frequency
dependent NLO proerties, for closed shell cases, see $TDHF.
==========================================================
==========================================================
$TDHF group (relevant for SCFTYP=RHF if RUNTYP=TDHF)
This group permits the analytic calculation of various
static and/or frequency dependent polarizabilities, with
an emphasis on important NLO properties such as second and
third harmonic generation. The method is programmed only
for closed shell wavefunctions, at the semiempirical or
ab initio level. Ab initio calculations may be direct SCF,
or parallel, if desired.
Because the Fock matrices computed during the time
dependent HartreeFock CPHF are not symmetric, you may not
use symmetry. You must enter NOSYM=1 in $CONTRL!
For a more general numerical approach to the static
properties, see $FFCALC.
NFREQ = Number of frequencies to be used. (default=1)
FREQ = An array of energy values in atomic units. For
example: if NFREQ=3 then FREQ(1)=0.0,0.1,0.25.
By default, only the static polarizabilities are
computed. (default is freq(1)=0.0)
The conversion factor from Hartree to wave
numbers is 219,474.6, and the wavelength is
given (in nm) by 45.56/FREQ.
MAXITA = Maximum number of iterations for an alpha
computation. (default=100)
MAXITU = Maximum number of iterations in the second order
correction calculation. This applies to iterative
beta values and all gammas. (default=100)
ATOL = Tolerance for convergence of firstorder results.
(default=1.0d05)
BTOL = Tolerance for convergence of secondorder results.
(default=1.0d05)
RETDHF = a flag to choose starting points for iterative
calculations from best previous results.
(default=.true.)
* * * the following NLO properties are available * * *
INIB = 0 turns off all beta computation (default)
= 1 calculates only noniterative beta
= 2 calculate iterative and noniterative beta
The next flags allow further BETA tuning
BSHG = Calculate beta for second harmonic generation.
BEOPE = Calculate beta for electrooptic Pockels effect.
BOR = Calculate beta for optical rectification.
INIG = 0 turns off all gamma computation (default)
= 1 calculates only noniterative gamma
= 2 calculate iterative and noniterative gamma
The next flags allow further GAMMA tuning
GTHG = Calculate gamma for third harmonic generation.
GEFISH = Calculate gamma for electricfield induced
second harmonic generation.
GIDRI = Calculate gamma for intensity dependent
refractive index.
GOKE = Calculate gamma for optical Kerr effect.
These will be computed only if a nonzero energy is
requested. The default for each flag is .TRUE., and they
may be turned off individually by setting some .FALSE.
Note however that the program determines the best way to
calculate them. For example, if you wish to have the SHG
results but no gamma results are needed, the SHG beta will
be computed in a noniterative way from alpha(w) and
alpha(2w). However if you request the computation of the
THG gamma, the second order U(w,w) results are needed and
an iterative SHG calculation will be performed whether
you request it or not, as it is a required intermediate.
Reference:
S.P.Karna, M.Dupuis J.Comput.Chem. 12, 487504 (1991).
P.Korambath, H.A.Kurtz, in "Nonlinear Optical Materials",
ACS Symposium Series 628, S.P.Karna and A.T.Yeates, Eds.
pp 133144, Washington DC, 1996.
Review: D.P.Shelton, J.E.Rice, Chem.Rev. 94, 329(1994).
==========================================================
==========================================================
$EFRAG group (optional)
This group gives the name and position of one or more
effective fragment potentials. It consists of a series of
free format card images, which may not be combined onto a
single line! The position of a fragment is defined by
giving any three points within the fragment, relative to
the ab initio system defined in $DATA, since the effective
fragments have a frozen internal geometry. All other atoms
within the fragment are defined by information in the
$FRAGNAME group.

1 a line containing one or more of these options:
COORD =CART selects use of Cartesians coords
to define the fragment position at
line 3. (default)
=INT selects use of Zmatrix internal
coordinates at line 3.
POLMETHD=SCF indicates the induced dipole for
each fragment due to the ab initio
electric field and other fragment
fields is updated only once during
each SCF iteration.
=FRGSCF requests microiterations during
each SCF iteration to make induced
dipoles due to ab initio and other
fragment fields self consistent
amoung the fragments. (default)
Both methods converge to the same
dipolar interaction.
POSITION=OPTIMIZE Allows full optimization within the
ab initio part, and optimization of
the rotational and translational
motions of each fragment. (default)
=FIXED Allows full optimization of the
ab initio system, but freezes the
position of the fragments. This
makes sense only with two or more
fragments, as what is frozen is the
fragments' relative orientation.
=EFOPT the same as OPTIMIZE, but if the
fragment gradient is large, up to
5 geometry steps in which only the
fragments move may occur, before
the geometry of the ab initio piece
is relaxed. This may save time by
reusing the two electron integrals
for the ab initio system.
MXBF = m maximum number of basis functions
in any of the EFP2 potentials (Pauli
repulsion and/or charge transfer).
MXMO = n maximum number of MOs in any of the
EFP2 potentials.
NBUFFMO = n First n orbitals in the MO matrix
are deemed to belong to the QM/MM
buffer and will be excluded from
the interaction with the EFP region.
This makes sense only if these first
MOs are frozen via the $MOFRZ group.
Input a blank line if all the defaults are acceptable.

2 FRAGNAME=XXX
XXX is the name of the fragment whose coordinates are to be
given next. All other information defining the fragment is
given in a supplemental $XXX group, which is referred to
below as a $FRAGNAME group.
Two different EFP1type water potentials are internally
stored. FRAGNAME=H2ORHF will select a water potential
developed at the RHF/DZP level, while FRAGNAME=H2ODFT will
select a potential corresponding to B3LYP/DZP (see $BASIS
for the precise meaning of DZP). If you choose one of
these internally stored potentials, you do not need to
input either a $FRAGNAME or $FRGRPL groups. (Note: prior
to 6/2005, the H2ORHF potential was called H2OEF2, a very
confusing name. The H2ORHF potential's parameters were not
changed when it was given its new name!)

3 NAME, X, Y, Z (COORD=CART)
NAME, I, DISTANCE, J, BEND, K, TORSION (COORD=INT)
NAME = the name of a fragment point. The name used
here must match one of the points in $FRAGNAME.
For the internally stored H2OEF2 and H2ODFT
potential, the atom names are O1, H2, and H3.
X, Y, Z = Cartesian coordinates defining the position of
this fragment point RELATIVE TO THE COORDINATE
ORIGIN used in $DATA. The choice of units is
controlled by UNITS in $CONTRL.
I, DISTANCE, J, BEND, K, TORSION = the usual Zmatrix
connectivity internal coordinate definition.
The atoms I, J, K must be atoms in the ab
initio system from in $DATA, or fragment points
already defined in the current fragment or
previously defined fragments.
Line 3 must be given a total of three times to define
this fragment's position.

Repeat lines 2 and 3 to enter as many fragments as you
desire, and then end the group with a $END line.
Note that it is quite typical to repeat the same fragment
name at line 2, to use the same fragment system at many
different positions.
==========================================================
* * * * * * * * * * * * * * * * * * * * *
For tips on effective fragment potentials
see the 'further information' section
* * * * * * * * * * * * * * * * * * * * *
==========================================================
$FRAGNAME group
(required for each FRAGNAME given in $EFRAG)
This group gives all pertinent information for a given
Effective Fragment Potential (EFP). This information falls
into three categories, with the first two shared by the
EFP1 and EFP2 models:
electrostatics (distributed multipoles, screening)
polarizability (distributed dipole polarizabilities)
The EFP1 model contains one final term,
fitted exchange repulsion
whereas the EFP2 model contains a collection of terms,
exchange repulsion, dispersion, charge transfer...
An Effective Fragment Potential is input using several
different subgroups. Each subgroup is specified by a
particular name, and is terminated by the word STOP. You
may omit any of the subgroups to omit that term from the
EFP. All values are given in atomic units.
To input monopoles, follow input sequence EM
To input dipoles, follow input sequence ED
To input quadrupoles, follow input sequence EQ
To input octopoles, follow input sequence EO
To input screening parameters, follow input sequence ES
To input polarizable points, follow input sequence P
To input fitted "repulsion", follow input sequence R
To input Pauli exchange, follow input sequence ÐPE
To input dispersion, follow input sequence ÐD
To input charge transfer, follow input sequence ÐCT
The data contained in a $FRAGNAME is normally generated by
performing a RUNTYP=MAKEFP using a standard $DATA group ab
initio computation on the desired solvent molecule. A
MAKEFP run will generate all terms for an EFP2 potential,
except the screening parameters. The screening option is
controlled by adding $DAMP and $DAMPGS groups, but is very
tricky to use, since it often finds unphysical screening
fits.
Note that the ability to fit the "repulsion" term in an
EFP1 potential is not included in GAMESS, meaning that EFP1
computations normally use builtin EFP1 water potentials.

1 a single descriptive title card

2 COORDINATES
COORDINATES signals the start of the subgroup containing
the multipolar expansion terms (charges, dipoles, ...).
Optionally, one can also give the coordinates of the
polarizable points, or centers of exchange repulsion.
3 NAME, X, Y, Z, WEIGHT, ZNUC
NAME is a unique string identifying the point.
X, Y, Z are the Cartesian coordinates of the point, and
must be in Angstrom units.
WEIGHT, ZNUC are the atomic mass and nuclear charge, and
are given only for the points which are nuclei.
Typically the true nuclei will appear twice, once for
defining the positive nuclear charge and its screening,
and a second time for defining the electronic distributed
multipoles.
Repeat line 3 for each expansion point, and terminate
the list with a "STOP".

EM1 MONOPOLES
MONOPOLES signals the start of the subgroup containing
the electronic and nuclear monopoles.
EM2 NAME, CHARGE1, CHARGE2
NAME must match one given in the COORDINATES subgroup.
CHARGE1 = electronic monopole at this point.
CHARGE2 = nuclear monopole at this point. Omit or enter
zero if this is a bond midpoint or some other
expansion point that is not a nucleus.
Repeat EM2 to define all desired charges.
Terminate this subgroup with a "STOP".

ED1 DIPOLES
DIPOLES signals the start of the subgroup containing the
dipolar part of the multipolar expansion.
ED2 NAME, MUX, MUY, MUZ
NAME must match one given in the COORDINATES subgroup.
MUX, MUY, MUZ are the components of the electronic dipole.
Repeat ED2 to define all desired dipoles.
Terminate this subgroup with a "STOP".

EQ1 QUADRUPOLES
QUADRUPOLES signals the start of the subgroup containing
the quadrupolar part of the multipolar expansion.
EQ2 NAME, XX, YY, ZZ, XY, XZ, YZ
NAME must match one given in the COORDINATES subgroup.
XX, YY, ZZ, XY, XZ, and YZ are the components of the
electronic quadrupole moment.
Repeat EQ2 to define all desired quadrupoles.
Terminate this subgroup with a "STOP".

EO1 OCTUPOLES (note: OCTOPOLES is misspelled)
OCTUPOLES signals the start of the subgroup containing
the octupolar part of the multipolar expansion.
EO2 NAME, XXX, YYY, ZZZ, XXY, XXZ,
XYY, YYZ, XZZ, YZZ, XYZ
NAME must match one given in the COORDINATES subgroup.
XXX, ... are the components of the electronic octopole.
Repeat EO2 to define all desired octopoles.
Terminate this subgroup with a "STOP".

ES1a SCREEN
SCREEN signals the start of the subgroup containing the
screening terms (A*exp[B*r**2]) for the distributed
multipoles, which account for charge penetration effects.
It pertains to ab initioEFP multipole interactions.
ES1b NAME, A, B
NAME must match one given in the COORDINATES subgroup.
A, B are the parameters of the Gaussian screening term.
Repeat ÐES1b to define all desired screening points.
Terminate this subgroup with a "STOP".

ES2a SCREEN2
SCREEN2 signals the start of the subgroup containing the
screening terms (A*exp[B*r]) for the distributed
multipoles, which account for charge penetration effects.
It pertains to EFPEFP multipole interactions.
ES2b NAME, A, B
NAME must match one given in the COORDINATES subgroup.
A, B are the parameters of the exponential screening term.
Repeat ES2b to define all desired screening points.
Terminate this subgroup with a "STOP".

P1 POLARIZABLE POINTS
POLARIZABLE POINTS signals the start of the subgroup
containing the distributed dipole polarizability tensors,
and their coordinates. This subgroup allows the
computation of the polarization energy.
P2 NAME, X, Y, Z
NAME gives a unique identifier to the location of this
polarizability tensor. It might match one of the points
already defined in the COORDINATES subgroup, but often does
not. Typically the distributed polarizability tensors are
located at the centroids of localized MOs.
X, Y, Z are the coordinates of the polarizability point.
They should be omitted if NAME did appear in COORDINATES.
The units are controlled by UNITS= in $CONTRL.
P3 XX, YY, ZZ, XY, XZ, YZ, YX, ZX, ZY
XX, ... are components of the distributed polarizability,
which is not a symmetric tensor. XY means dMUx/dFy, where
MUx is a dipole component, and Fy is a component of an
applied field.
Repeat P2 and P3 to define all desired polarizability
tensors, and terminate this subgroup with a "STOP".

The EFP1 model consists of a fitted potential, which is a
remainder term, after taking care of electrostatics and
polarization with the input described above. The fitted
term is called a "repulsive potential" because its largest
contribution stems from Pauli exchange repulsion. The fit
actually contains several other interactions, since it is
just a fit to the total interaction potential's remainder
after subtracting the elecrostatic and polarization
interactions.
The EFP2 model uses analytic representations for exchange
repulsion and other terms, and these are documented after
the EFP1's "repulsive potential".

R1 REPULSIVE POTENTIAL
See also the $FRGRPL input group, which defines the fit for
the EFP1EFP1 repulsion term.
REPULSIVE POTENTIAL signals the start of the subgroup
containing the fitted exchange repulsion potential, for the
interaction between the fragment and the ab initio part of
the system. This term also accounts, in part, for other
effects, since it is a fit to a remainder. The fitted
potential has the form
N
sum C * exp[D * r**2]
i i i
R2 NAME, X, Y, Z, N
NAME may match one given in the COORDINATES subgroup, but
need not. If NAME does not match one of the known points,
you must give its coordinates X, Y, and Z, otherwise omit
these three values. N is the total number of terms in the
fitted repulsive potential.
R3 C, D
These two values define the ith term in the repulsive
potential. Repeat line R3 for all N terms.
Repeat R2 and R3 to define all desired repulsive
potentials, and terminate this subgroup with a "STOP".

The following terms are part of the developing EFP2 model.
This model replaces the "kitchen sink" fitted repulsion in
the EFP1 model by analytic formulae. These formulae are to
be specific for each kind of physical interaction, and to
pertain to any solvent, not just water. The terms which
are programmed so far are given below.

PE1 PROJECTION BASIS SET
PE2 PROJECTION WAVEFUNCTION n m
PE3 FOCK MATRIX ELEMENTS
PE4 LMO CENTROIDS
These four sections contain the data needed to compute the
Pauli exchange repulsion, namely
1. the original basis set used to extract the potential.
2. the localized orbitals, expanded in that basis.
3. the Fock matrix, in the localized orbital basis.
4. the coordinates of the center of each localized orb.
The information generated by a MAKEFP that follows these
four strings is largely self explanatory. Note, however,
that the orbitals (PE2) must have two integers giving the
number of occupied orbitals Ðn and the size of the basis
Ðm. The largest Ðn and Ðm occuring in any fragment
group must be given in the $EFRAG group, as MXMO and MXBF,
respectively. The PE2 and PE3 subsections do not contain
STOP lines.

D1 DYNAMIC POLARIZABLE POINTS
DYNAMIC POLARIZABLE POINTS signals the start of the
subgroup containing the distributed imaginary frequency
dipole polarizability tensors, and their coordinates. This
information permits the computation of dispersion energies.
D2 NAME, X, Y, Z
NAME gives a unique identifier to the location of this
polarizability tensor. It might match one of the points
already defined in the COORDINATES subgroup, but often does
not. Typically the distributed polarizability tensors are
located at the centroids of localized MOs.
X, Y, Z are the coordinates of the polarizability point.
They should be omitted if NAME did appear in COORDINATES.
The units are controlled by UNITS= in $CONTRL.
D3 XX, YY, ZZ, XY, XZ, YZ, YX, ZX, ZY
XX, ... are components of the distributed polarizability,
which is not a symmetric tensor. XY means dMUx/dFy, where
MUx is a dipole component, and Fy is a component of an
applied field.
Repeat D2 and D3 to define all desired polarizability
tensors, and then repeat for all desired imaginary
frequencies. MAKEFP jobs use 12 imaginary frequencies at
certain internally stored values, to enable quadrature of
these tensors, to form the C6 dispersion coefficient. Thus
D2 and D3 input is repeated 12 times. Terminate this
subgroup with a "STOP".

CT1 CANONVEC n m
CT2 CANONFOK
These two sections contain the data needed to compute the
charge transfer energy, namely
1. the canonical orbitals, expanded in the ÐPE1 basis.
2. the Fock matrix, in the canonical orbital basis.
The information generated by a MAKEFP that follows these
two strings is largely self explanatory. The MO and AO
sizes given by Ðn and Ðm have the same meaning as for the
ÐPE2 group. The CT1 group does not have a STOP line.

The EFP2 model presently can generate the energy for a
system with an ab initio molecule and EFP2 solvents, if
only Pauli exchange repulsion is used. The AIEFP gradient
for this term is not yet programmed, nor are there AIEFP
codes for dispersion or charge transfer. Thus use of the
EFP2 model, for all practical purposes, is limited to EFP
EFP interactions only, via COORD=FRAGONLY.
==========================================================
The entire $FRAGNAME group is terminated by a " $END".
==========================================================
$FRGRPL group
This group defines the interfragment repulsive potential
for EFP1 potentials. It accounts primarily for exchange
repulsions, but also includes charge transfer. Note that
the functional form used for the fragmentfragment
repulsion differs from that used for the ab initiofragment
repulsion, which is defined in the $FRAGNAME group. The
form of the potential is
N
sum A * exp[B * r]
i i i

1 PAIR=FRAG1 FRAG2
specifies which two fragment repulsions are being defined.
$FRAGNAME input for the two names FRAG1 and FRAG2 must have
been given.

2 NAME1 NAME2 A B
*or*
NAME1 NAME2 'EQ' NAME3 NAME4
NAME1 must be one of the "NAME" points defined in the
$FRAG1 group's REPULSION POTENTIAL section. Similarly
NAME2 must be a point from the $FRAG2 group. In addition,
NAME1 or NAME2 could be the keyword CENTER, indicating the
center of mass of the fragment.
A and B are the parameters of the fitted repulsive
potential.
The second form of the input allows equal potential fits to
be used. The syntax implies that the potential between the
points NAME1 and NAME2 should be taken the same as the
potential previously given in this group for the pair of
points NAME3 and NAME4.
If there are NPT1 points in FRAG1, and NPT2 points in
FRAG2, input line 2 should be repeated NPT1*NPT2 times.
Terminate the pairs of potentials with a "STOP" card.
Any pairs which you omit will be set to zero interaction.
Typically the number of points on which fitted potentials
might be taken to be all the nuclei in a fragment, plus
the center of mass.

Repeat lines 1 and 2 for all pairs of fragments, then
terminate the group with a $END line.
==========================================================
==========================================================
$PRTEFP group (optional)
This group provides control for generating integer
charge EFP fragments for constructing large EFPs. See
P.A.Molina, H.Li, J.H.Jensen J.Comput.Chem. 24, 19711979
(2003)
This group is mainly used in RUNTYP=MAKEFP runs. However,
in MOPAC RUNTYP=ENERGY runs, the presence of a $PRTEFP
group causes AM1 or PM3 charges to be printed and
punched out in a suitable format for EFP calculations.
NOPRT = an array specifying the atoms for which EFP
multipole and polarizability points will not be
printed/punched out.
Example: For a molecule with the connectivity
A1A2A3A4A5, NOPRT(1)=4,5 means that multipoles
centered on atoms 4 and 5, and bond midpoints BO34
and BO45 are not part of the EFP.
MIDPRT = an array specifying atoms whose bond midpoints
neglected by using NOPRT should be printed out.
Example: MIDPRT(1)=3 forces the printout of bond
midpoint BO34.
The neglect of monopoles leads to EFPs with
overall noninteger charge. The next keyword
defines "collection points" to which the removed
monopoles are added. Thus, the net charge of the
EFP=ICHARG. The presence of this "fictitious"
charge is compensated for by adding an opposing
dipole to the collection point.
NUMFFD = an array that defines (1) a collection point,
(2) the number of atoms contributing to monopoles
to this point, and (3) the numbers of the atoms.
More than one collection point can be defined.
An opposing dipole is calculated as 0.5Q*r (Q =
sum of neglected monopoles, r = distance between
collection point and nearest neglected monopole)
and placed at the collection point.
Example: NUMFFD(1)=3,2,4,5. The sum of monopoles
at A4, A5, BO34 and BO45 (Q) is added to the A3
monopole. A dipole, 0.5Q*r, is placed on A3,
where r is the distance between A3 and BO34.
If MIDPRT(1)=3, Q does not include the BO34
monopole, r is the distance between BO34 and A4,
and the resulting dipole is centered on BO34.
==========================================================
==========================================================
$DAMP group (optional, relevant if RUNTYP=MAKEFP)
This group provides control over the screening of the
distributed multipole expansion used by the EFP model for
the electrostatic interaction, to account for charge
penetration. See M.A.Freitag, M.S.Gordon, J.H.Jensen,
W.A.Stevens, J.Chem.Phys. 112, 73007306(2000). The
screening exponents are optimized by fitting a damped
multipolar electrostatic potential to the actual quantum
mechanical potential of the wavefunction. The fit is done
on a Cartesian grid lying between inner and outer spheres
on each atom.
Two different damping functions can be generated. The
first contains a single exponential form (1  exp(a*r))
where a varies, and initial guess values for a are given
in $DAMPGS. The second function is a single Gaussian
form, (1  b*exp(a*r**2)) where the initial values for a
are taken from a STO1G fit to the final values of the
exponential fit. The exponential fit is used for fragment
fragment charge penetration screening, while the Gaussian
fit is used in ab initiofragment screening. See equations
28 and 4 in the reference.
If $DAMP is not given, the rather time consuming
screening fit is skipped, while giving an empty $DAMP is
sufficient to trigger the fitting.
IFTTYP = 2 means generate an exponential fit, for use as
SCREEN2 input in $FRAGNAME.
= 0 means generate a Gaussian fit, for use as
SCREEN input in $FRAGNAME.
The default is to do both fits, IFTTYP(1)=2,0.
IFTFIX = 0 means the coefficients in the fit (b) are
free parameters
1 means the coefficients are held to unity.
In case the linear coefficients become large,
and particularly if they are negative, a fit
with unit coefficients is more reasonable.
The default is IFTFIX(1)=1,0.
VDWRAD = an array of van der Waals radii for each atom in
the molecule. Defaults are taken from Emsley's
yellow book, "The Elements" so are not built in
for exotic elements like transition metals.
RMIN1 = the minimum radius scale factor for each atom, for
the Gaussian fitting steps. (default=0.67)
RMAX1 = the maximum radius scale factor for each atom, for
the Gaussian fitting steps. (default=3.00)
RMIN2 = the minumum radius scale factor for each atom, for
the exponential fittings. The reference paper
suggests use of 67% of the van der Waals radius.
(default=0.67)
RMAX2 = the maximum radius scale factor for each atom, for
the exponential fittings. The reference paper
suggests use of 300% of the van der Waals radius.
(default=3.00)
XGRID = spacing between grid points (default = 0.5 a.u.)
MAXIT = maximum number of iterations in the fitting step.
The default is 10000.
THRSH = printing threshold for large deviations. The
default is 4.0 kcal/mol.
==========================================================
==========================================================
$DAMPGS group (relevant if $DAMP was given)
This is a freeformat, line by line input group that
sets the initial values (guess) for the first damping
function used to screen the multipole expansion. The
initial guess for the second fit will be taken from the
final values of the first fit.
Each multipole expansion point (typically all atoms
followed by all bond midpoints) should receive a value.
A check run may be helpful in listing the names of the
expansion points that are chosen by MAKEFP jobs.

1
'EQ'
This line gives the name of the expansion point, and how
many terms are in the damping function. You must enter 1
for the number of terms. The second form of this line lets
you equate the current point to some previous point's
values in $DAMPGS, skipping line 2.

2
The linear coefficient and exponent of this term in the
damping function. Repeat input for 2 times.
You must enter the coefficient as 1.0 at the present.
If the integer is omitted or given as 0, the
exponents are optimized, but entering 1 freezes these.

Repeat 1 and 2 until all multipole centers receive
their initial guess parameters.
==========================================================
==========================================================
$PCM group (optional)
This group controls solvent effect computations using
the Polarizable Continuum Model. If this group is found in
the input file, a PCM computation is performed. The
default calculation, chosen by selecting only the SOLVNT
keyword, is to compute the electrostatic free energy.
Appropriate numerical constants are provided for a wide
range of solvents. Additional keywords allow for more
sophisticated computations, namely cavitation, repulsion,
and dispersion free energies. The methodology for these is
general, but only numerical constants for water are
provided. There is additional information on PCM in the
References chapter of this manual.
Pure PCM calculations (meaning solute plus PCM continuum
energy and/or gradients) are programmed for RHF, ROHF, UHF,
GVB, and MCSCF wavefunctions, and their DFT counterparts,
but not for MP2, CI, or Coupled Cluster, or for MOPAC runs.
The same wavefunctions may be used to compute the energy of
a solute + EFP explicit solvent molecules + PCM continuum.
The only PCM method prior to Oct. 2000 was DPCM, which
can be recovered by selecting IEF=0 and ICOMP=2 in $PCM.
The default PCM method between Oct. 2000 and May 2004 was
IEFPCM, recoverable by IEF=3 (but 3 for nongradient
runs) and ICOMP=0. As of May 2004, the default PCM method
was changed to CPCM (IEF=10, ICOMP=0). The extension of
PCM to all SCFTYPs as of May 2004 involved a correction to
the MCSCF PCM operator, so that it would reproduce RHF
results when run on one determinant, meaning that it is
impossible to reproduce prior MCSCF PCM calculations.
The cavity definition was GEPOLGB (MTHALL=1 in $TESCAV)
prior to May 2004, and GEPOLAS thence (MTHALL=2). The
option for generation of 'extra spheres' (RET in $PCM) was
changed from 0.2 to 100.0, to suppress these, in June 2003.
 the first set of parameters controls the computation:
IEF, ICOMP, ICAV, IDISP, IREP, IDP, and IFIELD.
Note: IDISP, IREP, IDP can only be used with RHF.
IEF switch to choose the type of PCM model used.
The default is Ð10.
= 0 isotropic dielectrics using the original
formulation of PCM for dielectrics (DPCM)
= 1 anisotropic dielectric using the Integral
Equation Formalism (IEF) of PCM, see $IEFPCM
= 2 ionic solutions using IEFPCM, see $IEFPCM
= 3 isotropic dielectrics using IEFPCM with matrix
inversion solver, see $IEFPCM
= 3 isotropic dielectric IEFPCM with iterative
solver, see $PCMITR.
= 10 conductorlike PCM (CPCM) with matrix
inversion. Charge scaling is(Eps1.0)/Eps
=10 CPCM, with iterative solver. See $PCMITR.
The value of IPCDER in $PCMGRD controlling the gradient
computational method is related to IEF, according to
IEF= 3 may choose only IPCDER=0,1
IEF=3 may choose from IPCDER=0,1,2
Options IEF=1 or 2 are incompatible with gradients and also
must choose ICOMP=0. IEF=3 may not choose ICOMP=3, but if
diffuse functions are in use, this IEF choice may benefit
from ICOMP=2. The DPCM method (IEF=0) should normally
choose ICOMP=2. Geometry optimization with PCM might not
be able to converge well using the original GEPOLGB
tessellation of the cavity surface, but GEPOLAS or GEPOL
RT should result in much crisper geometry convergence, at
some cost in machine time, see $TESCAV. The iterative
solvers chosen by IEF=3 or 10 usually reproduce the
energy of IEF=3 or 10 to within 1.0d5 Hartrees, but will
be much faster and use less memory for large molecules.
*** at the present time, there is a bug with IEF=1 or 2.
ICOMP = Compensation procedure for induced charges.
Gradient runs require ICOMP be 0 or 2 only.
= 0 No. (default)
= 1 Yes, each charge is corrected in proportion
to the area of the tessera to which it belongs.
= 2 Yes, using the same factor for all tesserae.
= 3 Yes, with explicit consideration of the
portion of solute electronic charge outside
the cavity, by the method of Mennucci and
Tomasi. See the $NEWCAV group.
ICAV = At the end of the run, calculate the cavitation
energy, by the method of Pierotti and Claverie:
= 0 skip the computation (default)
= 1 perform the computation.
If ICAV=1, the following parameter is relevant:
TABS = the absolute temperature, in units K.
(default=298.0)
There are two procedures for the calculation
of the repulsion and dispersion free energy.
IDISP is incompatible with IREP and IDP.
IDISP = Calculation of both dispersion and repulsion
free energy through the empirical method of
Floris and Tomasi.
= 0 skip the computation (default)
= 1 perform the computation. See $DISREP group.
The next two options add repulsive and dispersive terms
to the solute hamiltonian, in an ab initio manner, by
the method of Amovilli and Mennucci.
IREP = Calculation of repulsion free energy
= 0 skip the computation (default)
= 1 perform the computation. See $NEWCAV group.
IDP = Calculation of dispersion free energy
= 0 skip the computation (default)
= 1 perform the computation. See $DISBS group.
If IDP=1, then three additional parameters must be
defined. The two solvent values correspond to water,
and therefore these must be input for other solvents.
WA = solute average transition energy. This is
computed from the orbital energies for RHF,
but must be input for MCSCF runs.
(default=1.10)
WB = ionization potential of solvent, in Hartrees.
(default=0.451)
ETA2 = square of the zero frequency refractive index
of the solvent. (default=1.75)
IFIELD = At the end of a run, calculate the electric
potential and electric field generated by the
apparent surface charges.
= 0 skip the computation (default)
= 1 on nuclei
= 2 on a planar grid
If IFIELD=2, the following data must be input:
AXYZ,BXYZ,CXYZ = each defines three components of the
vertices of the plane where the reaction
field is to be computed (in Angstroms)
A ===> higher left corner of the grid
B ===> lower left corner of the grid
C ===> higher right corner of the grid
NAB = vertical subdivision (AB edge) of the grid
NAC = horizontal subdivision (AC edge) of the grid.
 the next group of keywords defines the solvent
SOLVNT = keyword naming the solvent of choice. The eight
numerical constants defining the solvent are
internally stored for the following:
WATER (or H2O)
CH3OH C2H5OH
CLFORM (or CHCl3) CTCL (or CCl4)
METHYCL (or CH2Cl2) 12DCLET (or C2H4Cl2)
BENZENE (or C6H6) TOLUENE (or C6H5CH3)
CLBENZ (or C6H5Cl) NITMET (or CH3NO2)
NEPTANE (or C7H16) CYCHEX (or C6H12)
ANILINE (or C6H5NH2) ACETONE (or CH3COCH3)
THF DMSO (or DMETSOX)
The default solvent name is "INPUT" which means
you must give the following 8 numerical values:
RSOLV = the solvent radius, in units Angstrom
EPS = the dielectric constant
EPSINF = the dielectric constant at infinite frequency.
This value must be given only for RUNTYP=TDHF,
if the external field frequency is in the optical
range and the solvent is polar; in this case the
solvent response is described by the electronic
part of its polarization. Hence the value of the
dielectric constant to be used is that evaluated
at infinite frequency, not the static one (EPS).
For nonpolar solvents, the difference between
the two is almost negligible.
TCE = the thermal expansion coefficient, in units 1/K
VMOL = the molar volume, in units ml/mol
STEN = the surface tension, in units dyne/cm
DSTEN = the thermal coefficient of log(STEN)
CMF = the cavity microscopic coefficient
Values for TCE, VMOL, STEN, DSTEN, CMF need to be given
only for the case ICAV=1. Input of any or all of these
values will override the internally stored value.
 the next set of keywords defines the molecular cavity
NESFP = the number of initial spheres.
(default = number of atoms in solute molecule)
ICENT = option for definition of initial spheres.
= 0 centers spheres on each nucleus. (default)
= 1 sphere centers XE, YE, ZE and radii RIN will be
specified explicitly in $PCMCAV.
The cavity generation algorithm may use additional
spheres to smooth out sharp grooves, etc. The
following parameters control how many extra spheres
are generated:
OMEGA and FRO = GEPOL parameters for the creation of the
'added spheres' defining the solvent accessible
surface. When an excessive number of spheres is
created, which may cause problems of convergence,
the value of OMEGA and/or FRO must be increased.
For example, OMEGA from 40 to 50 ... up to 90,
FRO from 0.2 ... up to 0.7.
(defaults are OMEGA=40.0, FRO=0.7)
RET = minimum radius (in A) of the added spheres.
Increasing RET decreases the number of added
spheres. A value of 100.0 (default) inhibits the
addition of any spheres, while 0.2 fills in many.
IPRINT = 0 normal printing (default)
= 1 turns on debugging printout
==========================================================
==========================================================
$PCMGRD group (optional)
This group controls the PCM gradient computations.
IPCDER = selects different methods for PCM gradients
= 0 fixedcavity approximation
Implemented only for CPCM and IEFPCM
1 use Ux(q) approximation (CPCM and IEFPCM)
or use chargederivative method (DPCM).
This is the default for DPCM
2 VariableTesseraNumber Approximation
Implemented only for CPCM and IEFPCM, and
the default for both of these.
note: If ICAV = 1 or IDISP = 1 in $PCM, the derivatives
of the cavitation energy or dispersionrepulsion,
respectively, will automatically be calculated.
These particular steps are evaluated numerically.
IFAST = Controls the PCM calculations for RUNTYP=OPTIMIZE.
0 update PCM charges at each SCF cycle at every
geometry (default)
1 update PCM charges at each SCF cycle for the
initial geometry.
For the subsequent geometries, calculate PCM
charges at the first SCF cycle and use the PCM
charges for the following SCF cycles; after
the density change falls below DENTOL, update
the PCM charges one time (to save CPU time).
==========================================================
==========================================================
$PCMCAV group (optional)
This group controls generation of the cavity holding
the solute during Polarizable Continuum Model runs.
The cavity is a union of spheres, according to ICENT and
associated input values given in $PCM. The data given
here must be given in Angstrom units.
XE,YE,ZE = arrays giving the coordinates of the spheres.
if ICENT=0, the atomic positions will be used.
if ICENT=1, you must supply NESFP values here.
RADII = VANDW selects van der Waals radii (Angstrom),
which is the default. VDW radii for atoms
H,He, B,C,N,O,F,Ne, Na,Al,Si,P,S,Cl,Ar,
K,As,Se,Br,Kr, Rb,Sb,Te,I, Cs,Bi
are internally tabulated, otherwise give RIN.
= VDWEFP, similar to VANDW, except that radii not
tabulated by VANDW are assigned as 1.60A.
This option is most useful for proteinEFP
calculations.
= SUAEFP, the simplified united atomic radii will be
be used for the array RIN, namely
H:0.01 C:1.77 N:1.68 O:1.59 P:2.10 S:2.10
For the other elements with Z<16, 1.50 is used.
For the elements with Z>16, 2.30 will be applied.
This is for the purpose of protein EFP calculations
note: Radii explicitly defined with RIN will overwrite the
defaults selected by VANDW, VDWEFP, or SUAEFP.
RIN = an array giving the sphere radii.
if ICENT=0, the program will look up the internally
data according to the RADII keyword.
if ICENT=1, give NESFP values.
ALPHA = an array of scaling factors, for the definition of
the solvent accessible surface. If only the first
value is given, all radii are scaled by the same
factor. (default is ALPHA(1)=1.2)
Example: Suppose the 4th atom in your molecule is Fe, but
all other atoms have van der Waals radii. You
decide a good guess for Fe is twice the covalent
radius: $PCMCAV RIN(4)=2.33 $END
The source for the van der Waals radii is "The Elements",
2nd Ed., John Emsley, Clarendon Press, Oxford, 1991,
except that for C,N,O, the U.Pisa's experience with the
best radii for PCM treatment of singly bonded C,N,O atoms
is used instead. The radii for a few transition metals
are given by A.Bondi, J.Phys.Chem. 68, 441451(1964).
==========================================================
==========================================================
$TESCAV group (optional)
This group controls the tessellation procedure for the
molecular surface in the PCM computations. The default
values for this group will normally be satisfactory. Use of
the GEPOLAS (best) or GEPOLRT mechanisms for dividing the
surface of the atomic spheres into tesserae will greatly
increase the chance of convergence for PCM geometry
optimizations. To converge to small OPTTOL values may take
a high density of tesserae on the cavity surface:
MTHALL=3 NTSALL=960 AREATL=0.0010 BONDRY=1000.0
This set of options may require raising the maximum number
of tesserae (MXTS) in the source code (see PROG.DOC). It
is reasonable to try just MTHALL=2 first, as this may be
sufficient w/o increasing the tesserae density. See also
IFAST=1 in $PCMGRD.
 The first two arrays control the density of tesserae
and the method to generate the tesserae.
INITS = array defines the initial number of tesserae for
each sphere. Only 60, 240 and 960 are allowed,
but the value can be different for each sphere.
(Default is INITS(1)=60,60,60,...) See NTSALL.
METHOD = array defining the tessellation method for each
sphere. The value can be different for each
sphere. The default is 2 for all spheres, e.g.
METHOD(1)=2,2,2,... See also MTHALL.
= 1 GEPOLGB, "GaussBonet" tessellation.
= 2 GEPOLAS, "area scaling" tessellation.
= 3 GEPOLRT, "regular tessellation".
 The next three parameters are presets for filling the
arrays INITS and METHOD with identical values.
NTSALL = 60, 240 or 960 (default = 60)
All values in the array INITS are set to NTSALL
MTHALL = 1, 2, or 3 (default = 2)
All values in the array METHOD are set to MTHALL
MTHAUT = 0 or 1 (default = 0)
If RUNTYP=OPTIMIZE and frozen atoms are defined
by IFCART, MTHAUT=1 will select METHOD=1 for
frozen atoms. See also AUTFRE and NTSFRZ.
note: Explicitly defining INITS and METHOD from the input
deck will overrule the presets from NTSALL, MTHALL
and/or MTHAUT.
 The following two parameters control GEPOLRT
AREATL = The area criterion (A*A) for GEPOLRT.
Tesserae with areas < AREATL at the boundary of
intersecting spheres will be neglected.
Default=0.010 A*A. Smaller AREATL cause larger
number of tesserae. AREATL < 0.00010 is not
recommended.
BONDRY = Controls (by scaling) the distance within which
tesserae are considered "close" to the boundary.
Such tesserae will be recursively divided into
smaller ones until their areas are < AREATL.
The default (= 1.0) means the distance is the
square root of the tessera area.
A large BONDRY value like 1000.0 will lead to
fine tessellation for the entire surface with
all tessera areas < AREATL.
 The next two parameters are only relevant if MTHAUT=1
AUTFRE = Distance (A) for frozen atoms to be treated as
moving atoms when MTHAUT=1. Default=2.0 A.
NTSFRZ = 60, 240 OR 960, initial tessera number for
frozen atoms. Default=60
==========================================================
==========================================================
$NEWCAV group (optional)
This group controls generation of the "escaped charge"
cavity, used when ICOMP=3 or IREP=1 in $PCM. This cavity
is used only to calculate the fraction of the solute
electronic charge escapes from the original cavity.
IPTYPE = choice for tessalation of the cavity's spheres.
= 1 uses a tetrahedron
= 2 uses a pentakisdodecahedron (default)
ITSNUM = m, the number of tessera to use on each sphere.
if IPTYPE=1, input m=30*(n**2), with n=1,2,3 or 4
if IPTYPE=2, input m=60*(n**2), with n=1,2,3 or 4
(default is 60)
*** the next three parameters pertain to IREP=1 ***
RHOW = density, relative to liquid water (default = 1.0)
PM = molecular weight (default = 18.0)
NEVAL = number of valence electrons on solute (default=8)
The defaults for RHOW, PM, and NEVAL correspond to water,
and therefore must be correctly input for other solvents.
==========================================================
==========================================================
$IEFPCM group (optional)
This group defines data for the integral equation
formalism version of PCM solvation. It includes special
options for ionic or anisotropic solutions.
The next two sets are relevant only for anisotropic
solvents, namely IEF=1:
EPS1, EPS2, EPS3 =
diagonal values of the dielectric permittivity
tensor with respect to the laboratory frame.
The default is EPS in $PCM
EUPHI, EUTHE, EUPSI =
Eulerian angles which give the rotation of the
solvent orientation with respect to the lab frame.
The term lab frame means $DATA orientation.
The default for each is zero degrees.
The next two are relevant to ionic solvents, namely IEF=2:
EPSI = the ionic solutions's dielectric, the default is
EPS from $PCM.
DISM = the ionic strength, in Molar units (mol/dm**3)
The default is 0.0
==========================================================
==========================================================
$PCMITR group (optional, for IEF=3 or 10 in $PCM)
This group provides control over the iterative
isotropic IEFPCM calculation. See
C.S.Pomelli, J.Tomasi, V.Barone
Theoret.Chem.Acc. 105, 446451(2001)
H.Li, C.S.Pomelli, J.H.Jensen
Theoret.Chem.Acc. 109, 7184(2003)
MXDIIS = Maximum size of the DIIS linear equations, the
value impacts the amount of memory used by PCM.
Memory=2*MXDIIS*NTS, where NTS is the number of
tesserae. MXDIIS=0 means no DIIS, instead the
point Jacobi iterative method will be used.
(Default=50)
MXITR1 = Maximum number of iters in phase 1. (Default=50)
MXITR2 = Maximum number of iters in phase 2. (Default=50)
note: if MXDIIS is larger than both MXITR1 and MXITR2
MXDIIS will be reset to be the larger of these two.
THRES = Convergence threshold for the PCM Apparent
Surface Charges (ASC). (Default=1.0D08)
THRSLS = Loose threshold used in the early SCF cycles when
the density change is above DENSLS. If THRSLS <
THRESH, this option is turned off.
Default is 5.0D04.
DENSLS = If the density change is above DENSLS the loose
threshold THRSLS applies. (Default = 0.01 au)
IDIRCT = 1, Directly compute the electronic potential at
each tessera and the ASC potential at the
electronic coordinates, with no disk storage.
(Default)
0, Compute and save above data to hard disk.
Keywords for region wise multipole expansion of ASCs
in approximating interaction among tesserae:
(C.S.Pomelli, J.Tomasi THEOCHEM 537, 97105(2001))
IMUL = Region wise multipole expansion order in the
approximate interaction among tesserae.
= 0, Neglected (Only for test purposes)
= 1, Monopole
= 2, Monopole+Dipole
= 3, Monopole+Dipole+Quadrupole (Default)
RCUT1 = Cutoff radius (Angstrom) for midrange
interactions among tesserae. Default=15.0 A
If RCUT1 is larger than your molecule, the
option is effectively turned off.
RCUT2 = Cutoff radius (Angstrom) for long range
interactions among tesserae. Default=30.0 A
The remaining keywords apply only to PCM calculations with
a QM/EFP solute (see Li et al.)
Keywords for region wise multipole expansion of ASCs
in approximating interaction between ASCs and QM region:
IMGASC = 1, Use region wise multipole expansion of ASCs
to compute the ASC potential at QM region.
0, no use of the multipole expansion method.
(default)
RASC = Cutoff radius (Angstrom) for used of the IMGASC
multipole expansion (Default=20.0 A)
Keywords for multipole expansion of the QM region in
approximating the QM region potential:
IMGABI = 0, multipole expansion of the QM region is turned
off (default).
1, turn multipole expansion of the QM region on.
RABI = Cutoff radius (Angstrom) for used of the IMGABI
multipole expansion (Default=4.0 A)
Keywords for the coupling of PCM and EFP polarizability
tensors:
IEFPOL = 1, PCM ASCs induce EFP dipoles.(default)
0, PCM ASCs do not induce EFP dipoles.
REFPOL = When IEFPOL=1, if the distance (Angstrom) between
a polarizability point and a tessera is less than
REFPOL, they are considered too close and the
field from the tessera will not induce dipole for
the polarizability point. Default=0.0 A means
always induce the dipole.
==========================================================
==========================================================
$DISBS group (optional)
This group defines auxiliary basis functions used to
evaluate the dispersion free energy by the method of
Amovilli and Mennucci. These functions are used only for
the dispersion calculation, and thus have nothing to do
with the normal basis given in $BASIS or $DATA. If the
input group is omitted, only the normal basis is used for
the IDP=1 dispersion energy.
NADD = the number of added shells
XYZE = an array giving the x,y,z coordinates (in bohr)
of the center, and exponent of the added shell,
for each of the NADD shells.
NKTYPE = an array giving the angular momenta of the shells
An example placing 2s,2p,2d,1f on one particular atom,
$DISBS NADD=7 NKTYP(1)= 0 0 1 1 2 2 3
XYZE(1)=2.9281086 0.0 .0001726 0.2
2.9281086 0.0 .0001726 0.05
2.9281086 0.0 .0001726 0.2
2.9281086 0.0 .0001726 0.05
2.9281086 0.0 .0001726 0.75
2.9281086 0.0 .0001726 0.2
2.9281086 0.0 .0001726 0.2 $END
==========================================================
==========================================================
$DISREP group (optional)
This group controls evaluation of the dispersion and
repulsion energies by the empirical method of Floris and
Tomasi. The group must be given with IDISP=1 in $PCM.
The two options are controlled by ICLAV and ILJ, only one
of which should be selected.
ICLAV = selects Claverie's disprep formalism.
= 0 skip computation.
= 1 Compute the solutesolvent disprep interaction
as a sum over atomatom interactions through a
Buckinghamtype formula (R^6 for dispersion,
exp for repulsion). (default)
Ref: PertsinKitaigorodsky "The atomatom
potential method", page 146.
ILJ = selects a LennardJones formalism.
= 0 skip computation. (default)
= 1 solute atom'ssolvent molecule interaction is
modeled by LennardJones type potentials, R^6
for dispersion, R^12 for repulsion).
 the following data must given for ICLAV=1:
RHO = solvent numeral density
N = number of atom types in the solvent molecule
NT = an array of the number of atoms of each type in a
solvent molecule
RDIFF = distances between the first atoms of each type
and the cavity
DKT = array of parameters of the disrep potential for
the solvent
RWT = array of atomic radii for the solvent
The defaults are chosen for water,
RHO=3.348D02
N=2
NT(1)=2,1
RDIFF(1)=1.20,1.50
DKT(1)=1.0,1.36
RWT(1)=1.2,1.5
DKA = array of parameters of the disrep potential for
the solute. Defaults are provided for some common
elements:
H: 1.00 Be: 1.00 B: 1.00 C: 1.00
N: 1.10 O: 1.36 P: 2.10 S: 1.40
RWA = array of atomic radii for the solute to compute
disrep. Defaults are provided for some common
elements:
H: 1.20 Be: 1.72 B: 1.72 C: 1.72
N: 1.60 O: 1.50 P: 1.85 S: 1.80
Other elements have DKA and RWA values of 0.0 and must be
given in the input deck, or the DISREP energy will be 0.
For EFP/PCM calculations, only QM atoms need DKA and RWA
values to calculate the DISREP energy.
 the following data must given for ILJ=1:
RHO = solvent numeral density
EPSI = an array of energy constants referred to each atom
of the solute molecule.
SIGMA = an array of typical distances, relative to each
solute atom
==========================================================
==========================================================
$SVP group (optional)
The presence of this group in the input turns on use of
the Surface and Simulation of Volume Polarization for
Electrostatics (SS(V)PE) solvation model, with isodensity
or spherical cavity, for RHF, UHF, ROHF, GVB, and MCSCF
wavefunctions. The energy is reported as a free energy,
which includes the factor of 1/2 that accounts for work of
solvent polarization. Gradients are not yet available.
Typical use of the SS(V)PE method will involve a prior
step to do an equivalent calculation on the given solute in
the gas phase. This provides a set of orbitals that can be
used as a good initial guess for the run including solvent.
It also provides the gas phase energy that can be
subtracted from the energy in solvent to obtain the
electrostatic contribution to the free energy of solvation.
Many runs will be fine with all parameters set at
their default values. The most important parameters a user
may want to consider changing are:
DIELST = static dielectric constant of solvent
(default = 78.39, appropriate for water)
ISHAPE = a flag to set the shape of the cavity surface
0  electronic isodensity surface (default)
1  spherical surface
RHOISO = value of the electronic isodensity contour used to
specify the cavity surface, in electrons/bohr**3
(relevant if ISHAPE=0; default=0.001)
RADSPH = sphere radius used to specify the cavity surface.
A positive value means it is given in Bohr,
negative means Angstroms. (relevant if ISHAPE=1;
default is half the distance between the
outermost atoms plus 1.4 Angstroms)
INTCAV = a flag to select the surface integration method
0  single center Lebedev integration (default)
1  single center spherical polar integration,
not recommended; Lebedev is far more efficient
NPTLEB = number of Lebedevtype points used for single
center surface integration. The default value
has been found adequate to obtain the energy to
within 0.1 kcal/mol for solutes the size of
monosubstituted benzenes. (relevant if INTCAV=0)
Valid choices are 6, 14, 26, 38, 50, 86, 110, 146,
170, 194, 302, 350, 434, 590, 770, 974, 1202,
1454, 1730, 2030, 2354, 2702, 3074, 3470, 3890,
4334, 4802, 5294, or 5810. (default=1202)
NPTTHE, NPTPHI = number of (theta,phi) points used for
single center surface integration. These should
be multiples of 2 and 4, respectively, to provide
symmetry sufficient for all Abelian point groups.
(relevant if INTCAV=1; defaults = 8,16; these
defaults are probably too small for all but the
tiniest and simplest of solutes.)
TOLCHG = a convergence criterion on the program variable
named CHGDIF, which is the maximum change in any
surface charge from its value in the previous
iteration (default=1.0D7). This is checked in
each SCF iteration, although the actual value
is not printed until final convergence is reached.
The singlecenter surface integration approach may fail for
certain highly nonspherical molecular surfaces. The program
will automatically check for this and bomb out with a
warning message if need be. The singlecenter approach
succeeds only for what is called a star surface, meaning
that an observer sitting at the center has an unobstructed
view of the entire surface. Said another way, for a star
surface any ray emanating out from the center will pass
through the surface only once. Some cases of failure may be
fixed by simply moving to a new center with the ITRNGR
parameter described below. But some surfaces are inherently
nonstar surfaces and cannot be treated with this program
until more sophisticated surface integration approaches are
implemented.
ITRNGR = translation of cavity surface integration grid
0  no translation (i.e., center the grid at the
origin of the atomic coordinates)
1  translate to center of nuclear mass
2  translate to center of nucl. charge (default)
3  translate to midpoint of outermost atoms
4  translate to midpoint of outermost
nonHydrogen atoms
5  translate to userspecified coordinates,
in Bohr
6  translate to userspecified coordinates,
in Angstroms
TRANX, TRANY, TRANZ = x,y,z coordinates of translated
cavity center, relevant if ITRNGR=5 or 6.
(default = 0,0,0)
IROTGR = rotation of cavity surface integration grid
0  no rotation
1  rotate initial xyz axes of integration grid to
coincide with principal moments of nuclear
inertia (relevant if ITRNGR=1)
2  rotate initial xyz axes of integration grid to
coincide with principal moments of nuclear
charge (relevant if ITRNGR=2; default)
3  rotate initial xyz axes of integration grid
through userspecified Euler angles as defined
by Wilson, Decius, Cross
ROTTHE, ROTPHI, ROTCHI = Euler angles (theta, phi, chi) in
degrees for rotation of the cavity surface
integration grid, relevant if IROTGR=3.
(default=0,0,0)
IOPPRD = choice of the system operator form. The default
symmetric form is usually the most efficient, but
when the number of surface points N is big it can
require very large memory (to hold two N by N
matrices). The nonsymmetric form requires solution
of two consecutive system equations, and so is
usually slower, but as tradeoff requires less
memory (to hold just one N by N matrix). The two
forms will lead to slightly different numerical
results, although tests documented in the third
reference given in Further Information show that
the differences are generally less than the
inherent discretization error itself and so are
not meaningful.
0 Ð symmetric form (default)
1 Ð nonsymmetric form
The remaining parameters below are rather specialized
and rarely of concern. They should be changed from their
default values only for good reason by a knowledgeable
user.
TOLCAV = convergence criterion on maximum deviation of
calculated vs. requested RHOISO
(relevant if ISHAPE=0; default=1.0D10)
ITRCAV = maximum number of iterations to allow before
giving up in search for isodensity surface.
(relevant if ISHAPE=0; default=99)
NDRCAV = highest analytic density derivative to use in the
search for isodensity surface.
0  none, use finite differences (default)
1  use analytic first derivatives
LINEQ = a flag to select the method for solving the linear
equations that determine the effective point
charges on the cavity surface.
0  use LU decomposition in memory if space
permits, else switch to LINEQ=2
1  use conjugate gradient iterations in memory if
space permits, else use LINEQ=2 (default)
2  use conjugate gradient iterations with the
system matrix stored externally on disk.
CVGLIN = convergence criterion for solving linear equations
by the conjugate gradient iterative method
(relevant if LINEQ=1 or 2; default = 1.0D7)
CSDIAG = a factor to multiply diagonal elements to improve
the surface potential matrix, S.
(default = 1.104, optimal for Lebedev integration)
IRDRF = a flag to read in a set of point charges as an
initial guess to the reaction field.
0  no initial guess reaction field (default)
1  read point charges from $SVPIRF input group.
It is up to the user to be sure that the
number of charges read is appropriate.
IPNRF = a flag to punch the final reaction field.
0  no punch (default)
1  punch in format of $SVPIRF input group
==========================================================
$SVPIRF group (optional; relevant for SVP runs)
Formatted card images of reaction field point charges, as
punched by setting IPNRF=1 in a previous SVP run. These can
be used by setting IRDRF=1 in a subsequent SVP run to
provide an initial guess to the reaction field.
==========================================================
==========================================================
$COSGMS group (optional)
The presence of this group in the input turns on the
use of the conductorlike screening model with molecular
shaped cavity for RHF and closed shell MP2. For RHF, the
energy and gradient can be computed, while MP2 is limited
to the energy only.
EPSI = the dielectric constant, 80 is often used for H2O
This parameter must be given.
RSOLV = the multiplicative factor for the van der Waals
radius used for cavity construction.
(default=1.2)
NSPA = the number of surface points on each atomic
sphere that form the cavity. (default=92)
Additional information on the COSMO model can be
found in the References chapter of this manual.
==========================================================
==========================================================
$SCRF group (optional)
The presence of this group in the input turns on the
use of the KirkwoodOnsager spherical cavity model for the
study of solvent effects. The method is implemented for
RHF, UHF, ROHF, GVB and MCSCF wavefunctions and gradients,
and so can be used with any RUNTYP involving the gradient.
The method is not implemented for MP2, CI, any of the
semiempirical models, or for analytic hessians.
DIELEC = the dielectric constant, 80 is often used for H2O
RADIUS = the spherical cavity radius, in Angstroms
G = the proportionality constant relating the solute
molecule's dipole to the strength of the reaction
field. Since G can be calculated from DIELEC and
RADIUS, do not give G if they were given.
==========================================================
Additional information on the SCRF model can be
found in the Further Information chapter.
==========================================================
$ECP group (required if ECP=READ in $CONTRL)
This group lets you read in effective core potentials,
for some or all of the atoms in the molecule. You can
use built in potentials for some of the atoms if you like.
This is a free format (positional) input group.
*** Give a card set 1, 2, and 3 for each atom ***
card 1 PNAME, PTYPE, IZCORE, LMAX+1
PNAME is a 8 character descriptive tag for this potential.
If it is repeated for a subsequent atom, no other
information need be given on this card, and cards
2 and 3 may also be skipped. The information
will be copied from the first atom by this PNAME.
Do not use the option to repeat the previously read
ECP for an atom with PTYPE=NONE, instead type "NONE"
over and over again.
PTYPE = GEN a general potential should be read.
= SBKJC look up the Stevens/Basch/Krauss/Jasien/
Cundari potential for this type of atom.
= HW look up the Hay/Wadt built in potential
for this type of atom.
= NONE treat all electrons on this atom.
IZCORE is the number of core electrons to be removed.
Obviously IZCORE must be an even number, or in other
words, all core orbitals being removed must be
completely occupied.
LMAX is the maximum angular momentum occupied in the
core orbitals being removed (usually). Give
IZCORE and LMAX only if PTYPE is GEN.
*** For the first occurence of PNAME, if PTYPE is GEN, ***
*** then give cards 2 and 3. Otherwise go to 1. ***
*** Card sets 2 and 3 are repeated LMAX+1 times ***
The potential U(LMAX+1) is given first,
followed by U(L)U(LMAX+1), for L=1,LMAX.
card 2 NGPOT
NGPOT is the number of Gaussians in this part of the
local effective potential.
card 3 CLP,NLP,ZLP (repeat this card NGPOT times)
CLP is the coefficient of this Gaussian in the potential.
NLP is the power of r for this Gaussian.
ZLP is the exponent of this Gaussian.
Note that PTYPE lets you to type in one or more atoms
explicitly, while using built in data for other atoms.
By far the easiest way to use the SBKJC potential for all
atoms in the formic acid molecule is to request ECP=SBKJC
in $CONTRL. But here we show two alternatives.
The first way is to look up the program's internally
stored SBKJC potentials one atom at a time:
$ECP
CECP SBKJC
HECP NONE
OECP SBKJC
OECP
HECP NONE
$END
The second oxygen duplicates the first, no core electrons
are removed on hydrogen. The order of the atoms must
follow that generated by $DATA. All atoms must be given
here in $ECP, not just the symmetry unique atoms.
The second example reads all SBKJC potentials explicitly:
$ECP
CECP GEN 2 1
1  CARBON U(P) 
0.89371 1 8.56468
2  CARBON U(S)U(P) 
1.92926 0 2.81497
14.88199 2 8.11296
HECP NONE
OECP GEN 2 1
1  OXYGEN U(P) 
0.92550 1 16.11718
2  OXYGEN U(S)U(P) 
1.96069 0 5.05348
29.13442 2 15.95333
OECP
HECP NONE
$END
Again, the 2nd oxygen copies from the first. It is handy
to use the rest of card 2 as a descriptive comment.
As a final example, for antimony we have LMAX+1=3 (there
are core d's). One must first enter U(f), followed by
U(s)U(f), U(p)U(f), U(d)U(f).
==========================================================
==========================================================
$MCP group (required if MCP READ was given on card 6U)
This group lets you read in model core potentials, for
some or all of the atoms in the molecule. This is a fixed
format input group. For the review of the MCP method, see
M.Klobukowski, Y.Sakai, and S.Huzinaga, pp. 4974 in J.
Leszczynski, "Computational Chemistry", vol. 3 (1999) .
*** Give input 1, 2, ..., 9 for each MCP atom ***
card 1 ANAT
ANAT is a 8 character name for the MCP atom.
It must match the name given for that atom
in the $DATA group.
card 2 NOAN, (NO(IS),NG(IS), IS=1,4) FORMAT(9I3)
IS = 1, 2, 3, 4 for s, p, d, and f symmetry, resp.
NOAN is the number of terms in the MCP
NO(IS) is the number of core orbitals in symmetry IS
NG(IS) is the number of basis functions used to
expand the core orbitals in symmetry IS
card 3 ZEFF, MCPFMT FORMAT(F10.2, A8)
ZEFF is the number of valence electrons, e.g. 7.0
for Fluorine
MCPFMT is the format for reading floatingpoint
numbers in the MCP data
card 4 (ACOEF(L), L=1,NOAN) FORMAT(MCPFMT)
ACOEF(L) is the Lth coefficient in the expansion of
the model core potential; more than one
line may be provided
ACOEF(L) is the defined as A(l) in Eq. (38)
of the MCP review paper.
card 5 (AEXPN(L), L=1,NOAN) FORMAT(MCPFMT)
AEXPN(L) is the Lth exponent in the expansion of the
model core potential; more than one line
may be provided
AEXPN(L) is the defined as alpha(l) in Eq.
(38) of the MCP review paper.
card 6 (NINT(L), L=1,NOAN) FORMAT(10I3)
NINT(L) is the power of R in the expansion of the
model core potential; NINT(L) is defined
as n(l) in Eq. (38) of the MCP review paper.
*** For each symmetry IS present in the core orbitals ***
*** read the card set 7, 8, and 9 ***
card 7 (BPAR(K), K=1,NO(IS)) FORMAT(MCPFMT)
BPAR(K) is the constant in the core projector
operator, B(k) in Eq. (41) of the review.
card 8 (EX(I), I=1,NG(IS)) FORMAT(MCPFMT)
EX(I) is the exponent of the Ith Gaussian
function used to expand the core orbitals
*** Repeat 9 for each core orbital in symmetry IS ***
card 9 (C(I), I=1,NG(IS)) FORMAT(MCPFMT)
C(I) expansion coefficients of the core orbital
The following example input file is for H2CO, and by
the way, provides another example of COORD=HINT.
!
$CONTRL RUNTYP=ENERGY COORD=HINT ECP=MCP $END
$DATA
Formaldehyde H2CO
CNV 2
C 6.0 LC 0.00 0.0 0.0  O K
MCP READ <<<< this is an MCP atom
L 3 <<<< (311/311/1) basis
1 18.517235 0.16370140 0.22673090E01
2 2.5787547 0.26304451 0.19109693
3 0.58994362 0.58040872 0.50918856
L 1
1 0.17330638 1.0000000 1.0000000
L 1
1 0.60957120E01 1.0000000 1.0000000
D 1; 1 0.600 1.0
O 8.0 LC 1.2031 0.0 0.0  O K
MCP READ <<<< this is an MCP atom
L 3 <<<< (311/311/1) basis
1 44.242510 0.13535836 0.17372951E01
2 6.2272700 0.30476423 0.16466813
3 1.4361751 0.43955753 0.46721611
L 1
1 0.40211473 1.0000000 1.0000000
L 1
1 0.12688798 1.0000000 1.0000000
D 1; 1 1.154 1.0
H 1.0 PCC 1.1012 121.875 0.0 + O K I
TZV <<<< not an MCP atom, TZV+pol basis
P 1; 1 1.100 1.0
$END
$MCP <<<< start of the MCP data
<<<< empty lines allowed
MCP for C NR (2S/2P) S(2)P(2) <<<< comment
<<<< empty lines allowed
C <<<< MCP for the atom C
2 1 14 <<<< NOAN, NO(1), NG(1)
4.00(4D15.8) <<<< ZEFF, MCPFMT
.41856306 .99599513E01 <<<< ACOEF
16.910482 7.4125554 <<<< AEXPN
0 0 <<<< NINT
22.676882 <<<< B(1s)
26848.283 8199.1206 2798.3668 1048.2982
423.36984 181.26843 81.068295 37.403931
17.629539 8.4254263 4.0611964 1.9672294
.95541420 .46459041
.10743274D03 .21285491D03 .99343100D03 .28327774D02
.83154481D02 .21694082D01 .52916004D01 .11618593D+00
.21812785D+00 .32180986D+00 .29375407D+00 .10974353D+00
.70844050D02 .17825971D02
MCP for O NR (2S/2P) S(2)P(4)
O <<<< MCP for the atom O
2 1 16
6.00(4D15.8)
.31002267 .27178756E01
25.973731 13.843290
0 0
41.361784
57480.749 17270.167 5766.9282 2107.0076
829.06758 346.04791 151.12147 68.233250
31.542773 14.815300 7.0298236 3.3561489
1.6077662 .77153240 .37052330 .17799002
.85822477D04 .18173691D03 .84803428D03 .25439914D02
.76877460D02 .20823429D01 .52424753D01 .11864010D+00
.22782741D+00 .33492260D+00 .28833079D+00 .93046197D01
.55937988D02 .16121923D02 .10915544D04 .21431633D03
$END
==========================================================
==========================================================
$RELWFN group (optional)
This group is relevant if RELWFN in $CONTRL chose one
of the relativistic transformations (DK, RESC, or NESC)
for elimination of the small components of relativistic
wavefunctions, to produce a corrected single component
wavefunction. For DK or RESC, only one electron integral
corrections are added, whereas for NESC, corrections to
two electron integrals are accounted for by means of a
relativistically averaged basis set. All relativistic
methods in GAMESS neglect twoelectron corrections coming
from pVp integrals. The 3rd order DK transformation will
normally afford the most sound results, from a theoretical
point of view.
Analytic gradients are programmed for both RESC and
NESC computations. For DK, all nonrelativistic gradient
terms are analytic, while the relativistic contributions
are evaluated numerically by a double difference formula.
During geometry optimizations, in rare cases, the
number of nearly linearly independent functions in the
Resolution of the Identity (RI) used to evaluate the most
difficult integrals may change at some new geometry. If
so, the job will quit with an error message, and the user
must restart it again manually.
For DK or RESC, ordinary basis sets are used. This
however is a misleading statement, for while any basis set
will run, accurate answers may be hard to obtain without
the use of basis sets constructed using the relativistic
approximations. Certainly at least the contraction coef
ficients must be modified to account for effects such as
the s orbital size contraction under relativity, but the
reoptimization of exponents may also be important. Early
experience suggests that large uncontracted basis sets
using nonrelativistic exponents are probably OK, but
standard contractions from NR atomic calculations can lead
to spurious results. As a rule of thumb, elements HXe
may be OK, but for heavier elements, use relativistically
derived basis sets. DK3 basis sets for HLr obtained at
U. of Tokyo exist in the form of general contractions,
http://www.chem.t.utokyo.ac.jp/appchem/labs/hirao/
publications/dk3bs/periodic_table.html
published by T.Tsuchiya, M.Abe, T.Nakajima, K.Hirao
J.Chem.Phys. 115,44634472(2001)
A program to extract this web page into GAMESS's format
is provided with GAMESS, see file ~/gamess/tools/dk3.f.
Light to medium atom main group (HKr) DK2 bases exist,
look for the names ccpVnZ_DK on
http://www.emsl.pnl.gov:2080/forms/basisform.html
For NESC, you must provide three basis sets, for the
large and small components and an averaged one, which are
given in $DATAL, $DATAS, $DATA, respectively. The only
possible choice for these basis sets is due to Dyall, and
these are available from
http://www.emsl.pnl.gov:2080/forms/basisform.html
Their names are similar to ccpVnZ(pt/sf/lc), pt=point or
fi=finite nucleus, sf for spinfree and the final field is
lc=large component ($DATAL), sc=small component ($DATAS),
and wf is a typo for FoldyWouthuysen 2e basis ($DATA).
In GAMESS you can only use point nucleus approximation.
The need to input three basis sets means that you cannot
use a $BASIS group, and you must use COORD=UNIQUE style
input in the various $DATA's. The three $DATA groups must
contain identical information except for the primitive
expansion coefficients, as the three basis sets must have
the same exponents. In case the option to treat only some
atoms relativistically is chosen, all nonrelativistic
atoms must have identical basis input in all three groups.
The finite size of nuclei is not taken into account, so
do not use any basis set obtained including this effect.
For NESC, the one electron part of the spinorbit
operator can be corrected, while for RESC, one can compute
spinorbit coupling with relativistic corrections to both
one and two electron SOC integrals, unless internal
uncontraction is requested (in this case only 1 electron
SOC integrals are modified). It should be noted that
internally uncontracted basis sets containing very large
exponents have large SOC integrals, thus the average
asymmetry due to RESC appears larger (before contraction).
For any order DK, the 1e SOC integrals are corrected only
to first order (DK1). It has been observed by many people
that even the first order correction is small, and thus it
should be sufficient.
* * * the next parameter applies only to RELWFN=DK:
NORDER gives the order of the DK transformation to be
applied to the oneelectron potential:
1 corresponds to the free particle
2 is the most commonly implemented DK method. It
has all relativistic corrections to second order.
(default)
3 represents 3rd order DK transformation. It does
not include all 3rd order relativity corrections,
in the sense of collecting all terms in the same
order of c (speed of light), due to using only a
2nd order form of the Coulomb potential (1/rij).
However, DK3 gives the closest approximation to
the DiracCoulomb equation of all methods here.
MODEQR is the mode of quasirelativistic calculation.
These options pertain to the DK or RESC methods.
The default is 1 (or 3 if ISPHER=1 in $CONTRL).
These are additive (bitwise) options, meaning you
must enter 5 to request options 1+4:
= 0 use the input contracted atomic basis set for
the Resolution of the Identity (RI) used to
simplify the pVp relativistic integrals in
order to evaluate them in closed form. Use of
this option will reproduce RESC results prior
to June 2001. As the accuracy of the RI is
compromised, this option is not recommended.
= 1 use the Gaussian primitives constituting the
input contracted atomic basis set to define the
RI. This produces a considerable increase in
accuracy of the integrals.
= 2 HONDO's implementation of the RI for RESC is
mimicked, namely for ISPHER=+1, the space used
for the RI will have no spherical contaminants,
similar to the MO space. This option is not
available for RESC gradients.
= 4 avoid redundant exponents when splitting L
shells into s and p, when generating the
internally uncontracted basis set. This is
necessary if you are using s or p primitives
with the same exponents as in some L shell.
This is unlikely to occur, but if so, the L
shell must be entered before the s or p.
Option 4 requires 1.
= 8 use 128 bit precision in the RIs. Select this
option if your exponent range is larger than 64
bits can handle (for example, if your basis
set's s primitive's exponents run from 1e+14 to
1e2, 16 orders, exhausting the 1416 decimal
places that 64 bits supports on most machines).
Note that setting this option also reduces
numerical noise in the gradient. This option
can be used with or without the internal
uncontraction.
1. 128 bit math can be very slow, depending
on your CPU and/or compiler's support for it.
Only relativistic 1e integrals use 128 bits.
2. If your FORTRAN library does not support the
REAL*16 data type (128 bits), the code compiles
itself in 64 bit mode, and will halt if you ask
for 128 bits.
NESOC = relativistic corrections for SOC integrals.
Relevant only if OPERAT=HSO1, HSO2P, or HSO2,
for RUNTYP=TRANSITN.
= 0 no corrections
= 1 oneelectron spinorbit integrals (NESC default)
= 2 one and twoelectron spinorbit integrals
(DK and RESC default). This is not programmed
for RESC with internal uncontraction (MODEQR=1),
so the program in this case will reset NESOC=1.
For RELWFN=RESC or NESC, relativistic SOC corrections
correspond to the same order as the spinfree Hamiltonian
transformation, that is, to second order.
For RELWFN=DK, no matter what NORDER is, SOC corrections
are obtained from the spindependent DK transformation
at 1st order.
NRATOM the number of different elements to be treated
nonrelativistically. For example, in Pb3O4, to
treat only lead relativistically, enter NRATOM=1.
The elements to be treated nonrelativistically are
defined by CHARGE. (default=0)
For NESC, this parameter affects the choice of the
basis sets, you should use identical large, small,
and averaged basis set for such atoms.
For DK or RESC, MODEQR=1 won't uncontract to the
primitives of such atoms.
CHARGE is an array containing nuclear charges of the atoms
to be treated nonrelativistically.
(e.g. CHARGE(1)=8.0, to drop all oxygen atoms)
CLIGHT gives the speed of light (atomic units), introduced
as a parameter in order to reproduce exactly results
published with a slightly different choice.
Default: 137.0359895
* * * the next parameters are used only with DK or RESC:
QMTTOL same as in $CONTRL, but used for the preparation of
the RI space. It is sensible to use a value smaller
than $CONTRL, if desired. (default: from $CONTRL).
QRTOL parameter for relativistic gradients.
RESC: tolerance for equating nearly degenerate
eigenvalues of the kinetic energy and overlaps,
when evaluating the gradient. Values that are too
large (>1e6) can cause numerical errors in the
gradient, approximately on the same order as QRTOL.
Too small values can add very large values to the
gradient due to division by numbers that are zero
within machine precision that are not avoided with
this tolerance filter. The recommended values for
MODEQR=1 are 1e6 for gold to 1e7 for silver.
For MODEQR=0, 1d8 or smaller can be used.
(default = smaller of 1d8 or QMTTOL).
DK: Coordinate offset in bohr for the numerical
differentiation of the relativistic contributions
to the gradient (analagous to VIBSIZ in $HESS, but
applied to gradients). Note that the offset is
applied to linear combinations of Cartesian
coordinates that conserve symmetry, and have the
translations and rotations projected out; the
change in Cartesian coordinates is equal to the
offset times the expansion coefficient.
Default: 1e2.
NVIB The number of offsets per coordinate (similar to
NVIB in $FORCE). NVIB can be 1 or 2 (or 1 or 2).
This parameter applies only to DK gradients.
Positive values correspond to the projected mode,
in which translations, rotations, and any modes
which are not totally symmetric are projected out.
Negative values correspond to using Cartesian
coordinates.
In most cases projected modes are superior; however
they can cause slight distortions away from the
true symmetry IF you specify lower symmetry than
the molecule actually possesses. (default=2)
==========================================================
==========================================================
$EFIELD group (not required)
This group permits the study of the influence of an
external electric field on the molecule. The method is
general, and so works for all wavefunctions, and both
energies and nuclear gradients.
EVEC = an array of the three x,y,z components of
the applied electric field, in a.u., where
1 Hartree/e*bohr = 5.1422082(15)d+11 V/m
SYM = a flag to specify when the field to be
applied breaks the molecular symmetry.
Since most fields break symmetry, so the
default is .FALSE.
==========================================================
Restrictions: analytic hessians are not available, but
numerical hessians are. Because an external field causes a
molecule with a dipole to experience a torque, geometry
optimizations must be done in Cartesian coordinates only.
Internal coordinates eliminate the rotational degrees of
freedom, which are no longer free.
Notes: a hessian calculation will have two rotational modes
with nonzero "frequency", caused by the torque. A gas
phase molecule will rotate so that the dipole moment is
antiparallel to the applied field. To carry out this
rotation during geometry optimization will take many steps,
and you can help save much time by inputting a field
opposite the molecular dipole. There is also a stationary
point at higher energy with the dipole parallel to the
field, which will have two imaginary frequencies in the
hessian. N.B., these will appear as the first two modes in
a hessian run, but will not have the i for imaginary
included on the printout since they are rotational modes.
For an application, see
H.Kono, S.Koseki, M.Shiota, Y.Fujimura
J.Phys.Chem.A 105, 56275636(2001)
Another use for this group is finite difference calculation
of the electric dipole. Perform two RUNTYP=ENERGY jobs per
component, with fields 0.001 and Ð0.001 a.u. The central
difference formula for each component of the dipole is
mu = 2.541766*(E(+0.001)E(0.001)/0.002, in Debye.
==========================================================
==========================================================
$INTGRL group (optional)
This group controls AO integral formats. Probably the
only values that should ever be selected are QFMM or
NINTIC, as the program picks sensible values otherwise.
QFMM = a flag to use the quantum fast multipole method
for linear scaling Fock matrix builds. This is
available for RHF, UHF, and ROHF wavefunctions,
and for DFT, but not with any other correlation
treatment. You must select DIRSCF=.TRUE. in
$SCF if you use this option. The RHF and closed
shell DFT gradients also uses QFMM techniques.
The Optimal Parameter FMM code will run at a
comparable speed to a ordinary run doing all
integrals for molecules about 15 Angstroms in
size, and should run faster for 20 Angstroms or
more. See also the $FMM group.
(default=.FALSE.)
SCHWRZ = a flag to activate use of the Schwarz inequality
to predetermine small integrals. There is no
loss of accuracy when choosing this option, and
there are appreciable time savings for bigger
molecules. Default=.TRUE. for over 5 atoms, or
for direct SCF, and is .FALSE. otherwise.
NINTMX = Maximum no. of integrals in a record block.
(default=15000 for J or P file, =10000 for PK)
NINTIC = Controls storage of integrals in memory, with
any remaining integrals will be stored on disk.
Caution: memory set aside for this parameter is
unavailable to the quantum chemistry methods.
Positive NINTIC indicate the number of integrals,
negative the amount of memory used for integrals
and labels (in words).
At present NINTIC works robustly for RHF, ROHF,
or UHF, is thought to work for GVB or MCSCF and
mostly works for sequential MP2 as well. Direct
SCF does not use this option! (default=0).
Various antiquated or antediluvian parameters follow:
NOPK = 0 PK integral option on, which is permissible
for RHF, UHF, ROHF, GVB energy/gradient runs.
= 1 PK option off (default for all jobs).
Must be off for anything with a transformation.
NORDER = 0 (default)
= 1 Sort integrals into canonical order. There
is little point in selecting this option, as
no part of GAMESS requires ordered integrals.
See also NSQUAR through NOMEM.
NSQUAR = 0 Sorted integrals will be in triangular
canonical order (default)
= 1 instead sort to square canonical order.
NDAR = Number of direct access logical records to be
used for the integral sort (default=2000)
LDAR = Length of direct access records (site dependent)
NBOXMX = 200 Maximum number of bins.
NWORD = 0 Memory to be used (default=all of it).
NOMEM = 0 If nonzero, force external sort.
The following parameters control integral restarts.
IST=JST=KST=LST=1 NREC=1 INTLOC=1
Values shown are defaults, and mean not restarting.
==========================================================
==========================================================
$FMM group (relevant if QFMM selected in $INTGRL)
This group controls the quantum fast multipole method
evaluation of Fock matrices. The defaults are reasonable,
so there is little need to give this input.
ITGERR = Target error in final energy, to 10**(ITGERR)
Hartree. The accuracy is usually better than
the setting of ITGERR, in fact QFMM runs should
suffer no loss of accuracy or be more accurate
than a conventional integral run (default=7).
QOPS = a flag to use the Quantum Optimum Parameter
Searching technique, which finds an optimum FMM
parameter set. (Default=.TRUE.)
If QOPS=.FALSE., the ITGERR value is not used. In this
case the user should specify the following parameters:
NP = the highest multipole order for FMM (Default=15).
NS = the highest subdivision level (Default=2).
IWS = the minimum wellseparateness (Default=2).
IDPGD = point charge approximation error (10**(IDPGD))
of the Gaussian products (Default=9).
IEPS = very fast multipole method (vFMM) error,
(10**(IEPS)) (Default=9)
==========================================================
==========================================================
$TRANS group (optional for CI or MCSCF)
(relevant to analytic hessians)
(relevant to energy localization)
This group controls the integral tranformation. MP2
integral transformations are controlled instead by the $MP2
input group. There is little reason to give any but the
first variable.
DIRTRF = a flag to recompute AO integrals rather than
storing them on disk. The default is .FALSE.
for MCSCF and CI runs. If your job reads $SCF,
and you select DIRSCF=.TRUE. in that group, a
direct transformation will be done, no matter
how DIRTRF is set.
Note that the transformation may do many passes over
the AO integrals for large basis sets, and thus the
direct recomputation of AO integrals can be very time
consuming.
CUTTRF = Threshold for keeping transformed two electron
integrals. (default= 1.0d9, except FMO=1.0d12)
IPURFY = orbital purification, like PURIFY in $GUESS.
= 0 skip orbital purification before transform.
= 1 perform purification once per geometry, for
example, in the first iteration of MCSCF only.
= 2 purify during every MCSCF iteration.
The default is 0. Use of 2 causes example 9 to
take one more iteration to converge, due to the
small upsetting of the orbitals between each
iteration by this purification. This option is
useful if PURIFY in $GUESS at the initial geometry
is insufficient purification.
NOSYM = disables the orbital symmetry test completely.
This is not recommended, as loss of orbital
symmetry is likely to mean a calculation is
turning into garbage. It has the same meaning
as the keyword in $CONTRL, but pertains to
just the integral transform. (Default is 0)
The remaining keywords refer almost entirely to the serial
integral transformation codes, not the distributed memory
routines:
MPTRAN = method to use for the integral transformation.
the default is try 0, then 1, then 2.
0 means use the incore method
1 means use the segmented method.
2 means use the alternate method, which uses
less memory than 2, but much more disk.
NWORD = Number of words of fast memory to allow. Zero
uses all available memory. (default=0)
AOINTS = AO integral storage during parallel runs.
It pertains only to CPHF=MO analytic Hessians.
DUP stores duplicated AO lists on each node.
DIST distributes the AO integral file across
all nodes.
==========================================================
==========================================================
$FMO group (optional, activates FMO option)
The presence of this group activates the Fragment
Molecular Orbital option, which divides large molecules
(think proteins or clusters) into smaller regions for
faster computation. The small pieces are termed 'monomers'
no matter how many atoms they contain. Calculations within
monomers, then 'dimer' pairs, and optionally 'trimer' sets
act so as to approximate the wavefunction of the full
system. The quantum model may be SCF, DFT, MP2 or MCSCF.
Sample inputs, and auxiliary programs, and other
information may be found in the GAMESS source distribution
in the directory ~/gamess/tools/fmo.
NBODY = nbody FMO expansion:
0 only run initial monomer guess (maybe remotely
useful to create the restart file, or as an
alternative to EXETYP=CHECK).
1 run up to monomer SCF
2 run up to dimers (default)
3 run up to trimers
I. The following parameters define layers.
NLAYER = the number of layers (default: 1)
MPLEVL = an array specifying n in MPn PT for each layer,
n=0 or 2. (default: all 0s).
Note that MCQDPT is not available and therefore
one may not choose this for MCSCF.
DFTTYP = an array specifying the DFT functional type for
each layer. (default: DFTTYP in $DFT).
See $DFT for possible functionals. Only grid
based DFT is supported (all functionals).
SCFTYP = an array specifying SCF type for each layer.
At present the only valid choices are RHF and
MCSCF (default: SCFTYP in $CONTRL for all).
CCTYP = an array specifying CC type for each layer, which
may be any CCTYP in $CONTRL, except the excited
state choices EOMCCSD and CREOM. It is better
to choose the size extensive methods, rather than
the renormalized options.
II. Parameters defining FMO fragments:
NFRAG = the number of FMO fragments (default: 1)
FRGNAM = an array of names for each fragment (each 18
character long) (default: FRG00001,FRG00002...).
INDAT = an array assigning atoms to fragments. Two styles
are supported (the choice is made based on
INDAT(1): if it is nonzero, choice (a) is taken,
otherwise INDAT(1) is ignored and choice (b) is
taken):
a) INDAT(i)=m assigns atom i is to fragment m.
INDAT(i) must be given for each atom.
b) the style is
a1 a2 ... ak 0
b1 b2 ... bm 0
...
Elements a1...ak are assigned to fragment 1,
then b1...bm are assigned to fragment 2,etc.
An element is one of the following:
I or I J
where I means atom I, and a pair I,J means
the range of atoms IJ. There must be no space
after the ""!
Example:
indat(1)=1,1,1,2,2,1 is equivalent to
indat(1)=0, 1,3,6,0, 4,5,0
Both assign atoms 1,2,3 and 6 to fragment 1,
and 4,5 to fragment 2.
ICHARG = an array of charges on the fragments
(default: all 0 charges)
MULT = an array of multiplicities for each fragment.
At most one fragment is allowed to differ from a
singlet, and then only for the MCSCF fragment.
(default: all 1's)
SCFFRG = an array giving the SCF type for each fragment
At present the only combination you can choose is
at most one is MCSCF and the rest must be RHF.
The values in SCFTYP overwrite SCFFRG, that is, if
you want to do a 2layer calculation, the first
layer being RHF and the other MCSCF, then you
would use SCFTYP(1)=RHF,MCSCF and SCFFRG(N)=MCSCF,
where you should replace N by your MCSCF fragment
number. Then the first layer will be all RHF and
the other will have one MCSCF fragment.
(default: SCFTYP in $CONTRL).
NOPFRG = printing and other fragmentspecific options,
these are additive options,
1 set the equivalent of $CONTRL NPRINT=7 (printing
option). Useful if you want to print orbitals
only for a few selected monomers.
2 set MVOQ to +6 to obtain better virtual orbitals
(ENERGY runs only, useful mostly to prepare good
initial orbitals for MCSCF).
4 generate cube file for the specified fragment,
the grid being chosen automatically.
(default: all 0s)
NACUT = automatically divides a molecule into fragments by
assigning NACUT atoms to each fragment (useful for
something like water clusters). This sets FRGNAM
and INDAT, so they need not be given. If 0, the
automatic option is disabled. (default: 0)
III. Parameters defining FMO approximations
RESPAP = cutoff for Mulliken atomic population approx,
namely, usage of diagonal terms only in ESPs.
It is applied if the distance between two monomers
is less than RESPAP, the distance is relative to
van der Waals radii; e.g. two atoms A and B
separated by R are defined to have distance in
waals equal to R/(RA+RB), where RA and RB are van
der Waals radii of A and B). RESPAP has no units,
as may be deduced from the formula. (default: 1.0)
RESPCC = cutoff for Mulliken atomic point charge approx,
namely replacing 2e integral contributions in ESPs
by effective 1e terms). See RESPAP. (default: 2.0)
RESDIM = cutoff for approximating the SCF energy by
electrostatic interaction (1e terms), see RESPAP.
This parameter must be nonzero for ab initio
electron correlation methods. (default: 2.0)
RCORSD = cutoff that is compared to the distance between
two monomers and all dynamic electron correlation
during the dimer run is turned off if the
distance is larger than this cutoff. RCORSD must
be less than or equal to RESDIM.
Note that SCF and DFT are not affected by RCORSD.
RCORSD must be given for MP2 and MCSCF, set it to
a large number (e.g., 100) if you do not want this
approximation.
(default: 2.0 for MP2 and 0.0 otherwise)
RITRIM = an array of 3 thresholds determining neglect of
3body terms. The exact definition can be found
in the source code.
Usage of three identical values is recommended.
(default: 2.0,2.0,2.0 if NBODY is 3, and
0.0,0.0,0.0 otherwise).
VDWRAD = array of van der Waals radii in Angstrom, one for
each atom in the periodic table. Reasonable values
are set only for a few light atoms and otherwise a
value of 2.5 is used. VDWRAD values are used only
to compute distance between fragments and thus
somewhat affect all distancebased approximations.
ORSHFT = orbital shift, the universal constant that
multiplies all projection operators. The value of
1e+8 was sometimes erroneously quoted instead of
the actual value of 1e+6 in some FMO publications.
(default: 1e+6).
MAXKND = the maximum number of LMO sets (one set is given
for each basis set located at the atoms where
bonds are fractioned). See also $FMOLMO.
(default: 10)
MAXCAO = the maximum number of LMOs in an LMO set.
(default: 5)
==========================================================
==========================================================
$FMOPRP group (optional for FMO
runs)
Options setting up SCF convergers, parallelization and
properties are given here.
I. Parameters for SCF convergers and initial guess
MAXIT = the maximum number of monomer SCF iterations.
(default 30)
CONV = monomer SCF energy convergence criterion.
It is considered necessary to set CONV in $SCF to
a value less or equal to the CONV in $FMO.
Usually 1e7 works well, but for poorly converging
monomer SCF (frequently seen with DFT) one order,
smaller value for CONV in $SCF is recommended,
(1e7 in $FMO and 1e8 in $SCF) (default: 1e7).
NGUESS = controls initial guess (cumulative options, add
all options desired) (default=2):
1 run free monomer SCF
2 if set, dimer density/orbitals are constructed
from the "sum" of monomer quantities, otherwise
Huckel guess will be used.
4 insert HMO projection operator in Huckel guess
8 apply dimer HO projection to dimer initial guess
16 do RHF for each dimer and trimer, then run DFT.
128 do not use orbitals from the previous geometry
during geometry optimization. This is mostly
useful for multilayer optimizations, when this
choice must always be set if basis sets differ .
512 reorder initial orbitals manually using $GUESS
options (IORDER), applies to MCSCF layers only.
IJVEC = Index array enabling reading $VEC groups defining
initial orbitals for individual runs (monomers and
dimers). This consists of pairs:
ifg1,jfg1, ifg2,jfg2, ...
The first pair indexes $VEC1 with ifg1,jfg1,
the second pair handles $VEC2 etc.
ifg,jfg defines a dimer if both are nonzero or
a monomer if jfg is zero. The first 0,0 pair ends
the list, which means if $VEC1, $VEC3, $VEC4 are
given only $VEC1 will be used.
(default: all 0s; at most 100 can be given)
MODORB = controls whether orbitals and energies are
exchanged between fragments (additive options).
1 exchange orbitals if set, otherwise densities
2 exchange energies
DFT requires MODORB=1 and MCSCF requires
MODORB=3, otherwise use MODORB=0.
Default: 0 for RHF, 1 for DFT, 3 for MCSCF.
MCONV = an array specifying SCF convergers for each FMO
step. Individually (MCONV(2) is for monomers,
MCONV(4) for dimers, MCONV(7) for trimers). Each
array element is set to A1+A2+A3, where A1
determines SCF and A2 MCSCF convergers, and A3 is
the direct/conventional bit common for all SCF
methods. MCONV is an additive option:
A1(SCF): A2(MCSCF): A3(direct)
1 EXTRAP 1024 FOCAS 256 FDIFF
2 DAMPH 2048 SOSCF 512 DIRSCF
4 VSHIFT 4096 DROPC
8 RSTRCT 8192 CANONC
16 DIIS 16384 FCORE
32 DEM 32768 FORS
64 SOSCF 65536 NOCI
131072 EKT
262144 LINSER
524288 JACOBI
1048576 QUD
There are some limitations on joint usage for each
that can be understood from $SCF or $MCSCF.
If set to 1, the defaults given in $SCF or $MCSCF
are used. See MCONFG. (default: all 1's).
MCONFG = an array specifying SCF convergers for each
fragment during the monomer SCF runs. The value 1
means use the default (defined by MCONV).
The priority in which convergers are chosen is:
MCONFG (highest), if not defined MCONV,
if not defined, $SCF (lowest).
This option is useful in case of poor convergence
caused by charge fluctuations and SCF converger
problems in particular, SOSCF instability for poor
initial guess. Default: all 1.
ESPSCA = scale factors for up to nine initial monomer SCF
iterations. ESPs will be multiplied by these
factors, to soften the effect of environment and
help convergence. At most nine factors can be
defined. (default: all 1.0's)
CNVDMP = damping of SCF convergence, that is, loosen
convergence during the initial monomer SCF
iterations to gain speed. CONV in $SCF and ITOL
and ICUT in $CONTRL are modified.
CONV is set roughly to min(DE/CNVDMP,1e4), where
DE is the convergence in energy at the given
monomer SCF iteration. It is guaranteed that
CONV,ITOL and ICUT at the end will be set to the
values given in $SCF. Damping is disabled if
CNVDMP is 0. Reasonable values are 10100.
Care should be taken for restart jobs: since
restart jobs do not know how well FMO converged,
restart jobs start out at the same rough values as
nonrestart jobs, if CNVDMP is used. Therefore for
restart jobs either set CNVDMP appropriately for
the restart (i.e., normally 10100 times larger
than for the original run) or turn this option
off, otherwise regressive convergence can incur
additional iterations (default: 0).
COROFF = parameter turning off DFT in initial monomer SCF,
similar to SWOFF. COROFF is used during monomer
SCF, and it turns off DFT until monomer energies
converge to this threshold. If COROFF is nonzero,
SWOFF is ignored during monomer SCF, but is used
for dimers and trimer iterations.
Setting both COROFF=1e3 and SWOFF=1e3 usually
produces good DFT convergence. If monomer SCF
converges poorly (>25 iterations), it is also
recommended to raise CONV in $SCF to 1e8 (if CONV
in $FMO is 1e7).
Default: 0 (do not use).
NCVSCF = an array of 2 elements to alter SCF convergers.
After NCVSCF(1) monomer SCF iterations the SCF
converger will switch between SOSCF <> FULLNR.
This option is useful in converging difficult
cases in the following way:
$SCF diis=.t. soscf=.f. $end
$FMOPRP NCVSCF(1)=2 mconv(4)=65 $end
This results in the initial 2 monomer SCF
iterations being done with DIIS, then a switch to
SOSCF occurs. mconv(4)=65 switches to SOSCF for
dimers.
Note that NCVSCF(1) will only overwrite MCONV, but
not MCONFG. The SCF converger in MCONV(2) will be
enforced after NCVSCF(2) monomer SCF iterations,
overwriting MCONFG as well. This is useful for
the most obnoxiously converging cases. See other
FMO documentation.
Default: 9999,9999 (which means do not use).
NAODIR = a parameter to decide whether to enforce DIRSCF.
Useful for incore integral runs in parallel.
NAODIR is the number of AO orbitals that is
expected to produce 100,000,000 nonzero
integrals. Using this and assuming NAO**3.5
dependence, the program will then guess how many
integrals will each nmer have and whether they
will fit into the available memory. If they are
determined not to fit, DIRSCF will be set true.
This option overwrites MCONV but not MCONFG.
If set to 0, then the default incore integral
strategy is used. (default=0)
II. Parameters defining parallel execution
MODPAR = parallel options (additive options)
1 turns on/off heavy job first strategy (reduces
waiting on remaining jobs at barrier points)
(see also 8)
2 changes ESP parallization strategy:
0 parallelise loops over shells in each fragment
2 parallelise loop over fragments
The former option is nearly always preferred.
4 broadcast all fragments done by a group at once
rather than fragment by fragment.
8 alters the behavior of fragment initialixation:
if set, fragments are always done in the reverse
order (nfg, nfg1, ...1) because distance
calculation costs decrease in the same order and
they usually prevail over making Huckel orbitals
or running free monomer SCF. Note that during
SCC (monomer SCF) iterations the order in which
monomers are done is determined by MODPAR=1.
16 if set, LMO projectors will not be parallelised
(may be seldom useful on slow networks)
32 reserved
64 Broadcast F40 for FMO restarts. F40 should only
be precopied to the grand master scratch
directory and it should NOT exist on all slaves.
(default: 13, which is 1+4+8)
NGRFMO = an array that sets the number of GDDI groups
during various stages of the calculation. The
first ten elements are used for layer 1, the next
10 for layer 2, etc.
ngrfmo(1) monomer SCF
ngrfmo(2) dimers
ngrfmo(3) trimers
ngrfmo(4) correlated monomers
ngrfmo(5) separated dimers
ngrfmo(6) SCF monomers in FMOMCSCF (MCSCF
monomer will be done with ngrfmo(1) groups)
ngrfmo(7) SCF dimers in FMOMCSCF (MCSCF dimer
be done with ngrfmo(2) groups)
ngrfmo(810) reserved
If any of them is zero, the corresponding stage
runs with the previously defined number of groups.
If NGRFMO option is used, it is recommended to set
NGROUP in $GDDI to the total number of nodes.
(default: 0,0,0,0).
MANNOD = manually define node division into groups.
Contrary to MANNOD in $GDDI and here it is defined
for each FMO stage (see NGRFMO) in each layer.
If MANNOD values are set at all, it is required
that they be given corresponding to the first
nonzero NGRFMO value. The MANNOD values should be
given for each nonzero NGRFMO.
E.g. ngrfmo(1)=6,3,0,0,0, 0,0,0,0,0, 4,3
mannod(1)=4,2,2,2,2,2, 5,5,4, 4,4,3,3, 6,6,2
where 6 groups are defined for monomers in layer
1, then 3 for dimers in layer 1, and 4 and 3
groups for monomers and dimers in layer 2.
(default: all 1 which means do not use).
III. Orbital conversion
File F40 that contains orbital density can be manipulated
in some way to change the information stored in it without
running any FMO calculations. Such conversion requires
irest=2 and the basis sets in the input should define the
old (before conversion) format. The results will be stored
in F30. You should then rename it to F40 and use in a
consequent run (with irest>=2).
Two basic conversion types are supported: A) changing RHF
into MCSCF and B) changing basis sets for RHF. RHF and
MCSCF use different stucture of the restart file (F40) and
therefore conversion is necessary.
For type A the following orbital reordering manipulation
before storing the results can be done, for example
$guess guess=modaf norder=1 iorder(28)=34,28
Type B is typically used for preparing good initial
orbitals for hard to converge cases. E.g., you can use
something like 621G to converge the orbitals and then
convert F40 to be used with 6311G*. At present there is a
limitation that only density based (MODORB=0) files may be
converged, i.e. you cannot do it for DFT and MCSCF.
MAXAOC = The new (i.e., after conversion) maximum number of
AOs per fragment. If you don't know what it should
be you can run a CHECK job with the new basis set
and find the number in "Max AOs per frg:".
If this number is equal to the old value, then
type A is chosen.
IBFCON = the array giving pairs of the old and new numbers
of AOs for each atom in $DATA (type B only).
MAPCON = maps determining how to copy old orbitals into new
(type B only). See the example.
Example: $DATA contains only H and O (in this order), F40
was computed with 631G and you want to convert to 631G**.
One water per fragment.
MAXAOC=25 25=5*2+15=new basis size for 631G**
IBFCON(1)=2,5, 9,15
2 and 5 for H (631 and 631G**), 9 and 15 for O
MAPCON(1)=1,2,0,0,0,
1,2,3,4,5,6,7,8,9,0,0,0,0,0,0
Here we copy the two s functions of each H, and add p
polarization p to each H (3 0's), and similarly we copy
nine s,p functions for O, and add d polarization (6 0's)
In order to construct MAPCON, you should know in what order
Gaussian primitives are stored. The easiest way to learn
this is to run a simple calculation and check the output
(SHELL information).
IV. Printing, properties, restart, and dimensions.
NPRINT = controls printout (bit additive)
bits 12
0 normal output
1 reduced output (recommended for single points)
2 minimum output (recommended for optimizations)
4 print interfragment distances. Note: any of
RESPAP, RESPPC, or RESDIM must be nonzero or
otherwise nothing will be printed. If you only
want the distances but no approximations, set
the thresholds to huge values, e.g. resdim=1000.
8 print Mulliken charges
Note: RESPPC must be set (nonzero), see above.
PRTDST = print all pairs of fragments separated by less
than PRTDST. See NPRINT. (default: 1.0)
IREST = restart level (all nonzero values require file
.F40 with restart data be precopied to each node).
(unless MODPAR=64 is set) See CNVDMP
0 no restart
2 restart monomer SCF (SCC).
4 restart dimers. Requires monomer energies be
given in $FMOENM. Some or no dimer energies
may also be given in $FMOEND, in which case
those dimers with energies will not be run.
Usually the only property that can be obtained
with IREST=4 is the energy. The only exception
is: a) IREST=1024 was set when monomer SCF was
run and b) the property restart files (*.F38*)
from each node were saved and copied to the
scratch directory for the IREST=1028 job. If
these two conditions are met, gradient and ES
moments can be restarted with IREST=1028.
1024 write property restart files during monomer SCF
and/or use them to restart gradient and/or ES
moments. No other property may be restarted.
Default: 0.
MODPRP = some extra FMO properties (bit additive)
1 total electron density (AObasis matrix, written
to F10: useful to create initial orbitals for ab
initio).
2 reserved.
4 electron density on a grid, produces a Gaussian
cube file.
8 electron density on a grid, produces a sparse cube
file.
16 automatically generate grid for modprp = 4 or 8.
Only one bit out of 4 and 8 may be set.
Default: 0.
NGRID = three integers, giving the number of 3D grid
points for monomers with NOPFRG=4 in x,y and z
directions (default 0,0,0).
GRDPAD = Grid padding. Contributions to density on grid
will be restricted to the box surrounding an nmer
with each atom represented by a sphere of GRDPAD
vdW radii. In general the finer effects one is
interested in, the larger GRDPAD should be. For
example, if one plots not density, but density
differences and a very small cutoff is used, then
a larger value of GRDPAD (2.5 or 3.0) may be
preferred.
Default: 2.0.
==========================================================
==========================================================
$FMOXYZ group (given for FMO runs)
This group provides an analog of $DATA for $FMO, except
that no explicit basis set is given here. It contains any
nonzero number of lines of the following type:
A.N Q X Y Z
A is the dummy name of an atom.
N is an optional basis set number (if omitted, it will be
set to 1). N is intended for mixed basis set runs, for
example, if you want to put diffuse functions on carboxyl
groups.
Q is the atomic charge.
Z is the integer atomic charge.
X, Y and Z are Cartesian coordinates. These obey UNITS
given in $CONTRL.
There is no default, this group must always be given for
FMO runs. Alternatively, you may use the chemical symbol
instead of Q. Note that "A" is ignored in all cases, but
must be given.
Here is how $DATA is used in FMO:
Each atom given in $DATA defines the basis set for that
atom type, entirely omitting Cartesian coordinates (which
are in $FMOXYZ). There are two ways to input basis sets in
FMO.
I. easy!
This works only if you want to use the same builtin basis
set for all atoms. It is possible to use EXTFIL as usual
for externally defined basis sets.
1. Define $BASIS as usual
2. Put each atom type in $DATA, e.g. for (H2O)2,
$DATA
H2O
C1 ! FMO does not support symmetry, so always use C1
H 1
O 8
$end
II. advanced.
This allows you to mix basis sets, have multiple layers or
a nonstandard without involving EXTFIL.
1. Do not define $BASIS.
2. Put each atom type in $DATA, followed by basis set,
either explicit or built in.
The names of atoms in $DATA have the following format,
where brackets indicate optional parameters:
S[.N][L]
N and L may be omitted (taking the default value of 1),
S is the atom name (discarded upon reading),
N is the basis set ordinal number,
L is the layer.
S[.N][L] may not exceed 8 characters.
Example: 2layer water dimer. In the first layer, you want
to use STO3G for the first molecule and your own basis set
for the second. In the second layer, you want to use 631G
and 631G* for the first and second molecules,
respectively.
$DATA
water dimer (H2O)2
C1
H1 1 ! explanation: layer 1, basis 1 (STO3G) for Hydr.
sto 3
O1 8 ! explanation: layer 1, basis 1 (STO3G) for Oxygen
sto 3
H.21 1 ! layer 1, basis 2 (manual) for hydrogen
s 1 ; 1 2.0 1
O.21 8 ! explanation: layer 1, basis 2 (manual) for Oxygen
s 2
1 100.0 0.8
2 10.0 0.6
l 1
1 5.0 1 1
H2 1 ! explanation: layer 2, basis 1 (631G) for Hydr.
n31 6
O2 8 ! explanation: layer 2, basis 1 (631G) for Oxygen
n31 6
H.22 1 ! layer 2, basis 2 (631G* = 631G) for Hydrogen
n31 6
O.22 8 ! explanation: layer 2, basis 2 (631G*) for Oxygen
n31 6
d 1 ; 1 0.8 1
$end
Your $FMOXYZ will then look as follows:
$FMOXYZ
O 8 x y z
H 1 x y z
H 1 x y z
O.2 8 x y z
H.2 1 x y z
H.2 1 x y z
$END
Note that if you define mixed basis sets for the atoms
where bond fractioning occurs (do not do this for basis
sets with diffuse functions), then you should provide all
required sets in $FMOLMO as well, and define $FMOBND
properly.
==========================================================
==========================================================
$OPTFMO group (relevant if RUNTYP=OPTFMO)
This group controls the search for stationary points
using optimizers developed for the Fragment Molecular
Orbital (FMO) method. There is no restriction on the number
of atoms in the molecule, whereas optimising FMO with
standard optimizers (RUNTYP=OPTIMIZE) has a restriction to
2000 atoms (unless you rebuild your GAMESS appropriately).
OPTFMO runs may be restarted by providing the updated
coordinates in $FMOXYZ and, optionally, optimization
restart data (punched out for each step) in $OPTRST (the
data differs for each method).
METHOD = optimization method
STEEP steepest descent
CG conjugate gradient
BFGSL approximate BFGS numeric updates of the
inverse Hessian, that do not require
explicitly storing that matrix.
HSSUPD numeric updates of the inverse Hessian
Default: HSSUPD.
HESS = initial inverse Hessian for METHOD=HSSUPD
GUESS diagonal guess of 3
READ read from F38 (advanced option)
Default: GUESS.
UPDATE = inverse Hessian update scheme for METHOD=HSSUPD
BFGS BroydenFletcherGoldfarbShanno
DFP DavidonFletcherPowell
Default: BFGS.
OPTTOL = gradient convergence tolerance, in Hartree/Bohr.
Convergence of a geometry search requires the
largest component of the gradient to be less
than OPTTOL, and the root mean square gradient
less than 1/3 of OPTTOL. (default=0.0001)
NSTEP = maximum number of steps to take. Restart data
are punched at each step. (default=200)
IFREEZ = array of coords to freeze during optimization.
The usage is the same as for the similar option in
$STATPT.
STEP = initial step factor. This multiplies the gradient
to prevent large steps. The values of 0.10.2 are
considered useful in the vicinity of minimum, and
0.51.0 is probably OK at the start. (default: 1)
STPMIN = the minimum permitted value of dynamically chosen
STEP size (see STPFAC). (default: 0)
STPMAX = the maximum permitted value of dynamically chosen
STEP size (see STPFAC). (default: 1)
STPFAC = Dynamic adjustment of STEP. If the energy goes
down considerably, the new STEP is set to the old
STEP multiplied by 1/STPFAC, if the energy goes up
significantly, STEP is set to STEP*STPFAC, both
constrained by STPMIN and STPMAX. The default is
1, which means do not use dynamic adjustment. The
value 0.9 may be useful if dynamically adjusted
steps are desired.
==========================================================
==========================================================
$FMOLMO group (optional, for FMO runs)
Localised molecular orbitals (LMO), used to describe bond
fractioning when dividing a molecule into fragments. One
set is given for each basis set used. In addition, a set
for the MINI basis set must be given. This group is not
required if no fractioned bonds are present, for example in
water clusters, where the FMO boundaries do not fraction
bonds.
Format:
NAM1 L1 M1
I1,1 J1,1 C1,1 C2,1 C3,1 ... CL1,1
...
I1,M1 J1,M1 C1,M1 C2,M1 C3,M1 ... CL1,M1
NAM2 L2 M2
I2,1 J2,1 C1,1 C2,1 C3,1 ... CL1,1
...
I2,M2 J2,M2 C1,M2 C2,M2 C3,M2 ... CL2,M2
where NAM are set names (up to 8 characters long), L1 is
the basis set size, M1 is the number of LMOs in this set.
Ci,j are LCAO coefficients (i is AO, j is MO) so it is the
transposed matrix of what is usually considered. Ii,j and
Ji,j are bond assignment numbers, defining to which side
the corresponding projection operator is added. Usually
one of each pair of I and J is 1, and the other 0.
(default: nothing, that is, no fractioned bonds).
==========================================================
==========================================================
$FMOBND group (optional, for FMO
runs)
The atom indices involved in the bond fractioning are
given, in pairs for each bond.
I1 J1 NAM1,1 NAM1,2 ... NAM1,n MINI
I2 J2 NAM2,1 NAM2,2 ... NAM2,n MINI
...
I and J are positive integers giving absolute atom indices.
NAMs are LMO set names, defined in $FMOLMO. MINI is always
the last. MINI set is used to construct initial guess
using orbitals. Each line is allowed to have different set
of NAMs, which can happen if different type of bonds are
fractioned, for example, one line describing CC bond and
another CN. Every bond given is fractioned in such a way
that the Iatom will get nothing of it, effectively remove
one electron (1/2 of a single covalent bond) from its
fragment. The Jatom will get all of the bond and thus adds
one electron to its fragment (e.g., formally heterolytic
assignment, although in practice all electrons remain
through the Coulomb field). The number 'n' above is the
number of layers.
(default: nothing, that is, no fractioned bonds).
Example, for a twolayer run with STO3G and 631G* in the
first and second layers, respectively.
$FMOBND
10 15 STO3G 631G* MINI
20 27 STO3G 631G* MINI
$END
==========================================================
==========================================================
$FMOENM group (optional, for FMO runs)
This group defines monomer energies for restart jobs. The
group should be taken from a previous run.
The format is IFG and ILAY, followed by 4 monomer energies,
of which only the first two are used (noncorrelated and
correlated).
IFG is the fragment number and ILAY is the layer number.
This group is required for FMO restarts IREST=4.
==========================================================
$FMOEND group (optional, for FMO runs)
Dimer energies for restart jobs. The group should be taken
from a previous run.
The format is IFG, JFG and ILAY, followed by 2 dimer
energies, (E'IJ and Tr(deltaDIJ*VIJ)). IFG and JFG describe
the dimer and ILAY is the layer number.
This group is optional for FMO restarts IREST=4 and is
otherwise ignored. Note that for parallel restarts,
$FMOEND groups from all nodes should be collected and
merged into one group.
==========================================================
$OPTRST group (optional, for RUNTYP=OPTFMO)
Restart data for FMO geometry optimizations. The data
inside vary for each optimization method, and are supposed
to be taken from a previous run (from the punch file).
==========================================================
==========================================================
$GDDI group (parallel runs only)
This group controls the partitioning of a large set of
processors into subgroups of processors, each of which
might compute separate quantum chemistry tasks. If there
is more than one processor in a group, the task assigned to
that group will run in parallel within that group. Note
that the implementation of groups in DDI requires that the
group boundaries be on SMP nodes, not individual
processors.
At present, the only procedure in GAMESS that can
utilize processor groups is the FMO method, which can farm
out different monomer or dimer computations to different
groups. This is advantageous, as the monomers are fairly
small, and therefore do not scale to very many processors,
although the monomer, dimer, and maybe trimer calculations
are numerous, and can be farmed out on a large parallel
system.
NGROUP = the number of groups in GDDI. Default is 0 which
means use standard DDI.
PAROUT = flag to create punch and log files for all nodes.
It is recommended to set this flag to .TRUE. if
you switch the number of groups on the fly (such
as in FMO).
BALTYP = load balancing at the group level, otherwise
similar to the one in $SYSTEM. BALTYP in $SYSTEM
is used for intragroup load balancing and the one
in $GDDI for intergroup. It is very seldom when
.FALSE. is useful (default: .FALSE.).
MANNOD = manual node division into groups, which is useful
for multihub networking. Provide an array of
group sizes, whose sum should be equal to NGROUP.
Note that this is nodes, that is, if you are using
six dualCPU nodes, you might enter
NGROUP=3 MANNOD(1)=2,2,2
so that four CPUs are in each subgroup. In other
words, the sum of MANNOD must equal the number of
SMP enclosures defined by ddikick.x.
Note on memory usage in GDDI. Memory is allocated for each
group individually. This means the same amount MEMDDI will
be used to allocate memory PER GROUP. Especially if you use
groups of various sizes, to avoid confusion it is
recommended that you set NGROUPs to the total number of
nodes so that you have one node per group and later you
switch to whatever group sizes you want (see $FMO).
==========================================================
The remaining groups apply only to MCSCF and CI runs.
* * * * * * * * * * * * * * * * * * *
For hints on how to do MCSCF and CI
see the 'further information' section
* * * * * * * * * * * * * * * * * * *
==========================================================
$CIINP group (optional, relevant for any CITYP)
This group is the control box for Graphical Unitary
Group Approach (GUGA) CI calculations or determinant based
CI. Each step which is executed potentially requires a
further input group described later.
NRNFG = An array of 10 switches controlling which steps of
a CI computation are performed.
1 means execute the module, 0 means don't.
NRNFG(1) = Generate the configurations. See either
$CIDRT or $CIDET input. (default=1)
NRNFG(2) = Transform the integrals. See $TRANS.
(default=1)
NRNFG(3) = Sort integrals and calculate the Hamiltonian
matrix. See $CISORT and $GUGEM. (default=1)
This does not apply to determinants.
NRNFG(4) = Diagonalize the Hamiltonian matrix.
See $GUGDIA or $CIDET. (default=1)
NRNFG(5) = Construct the one electron density matrix,
and generate NO's. See $GUGDM or $CIDET.
(default=1)
NRNFG(6) = Construct the two electron density matrix.
See $GUGDM2 or $CIDET.
(default=0 normally, but 1 for CI gradients)
NRNFG(7) = Construct the Lagrangian of the CI function.
Requires DM2 matrix exists. See $LAGRAN.
(default=0 normally, but 1 for CI gradients)
This does not apply to determinants.
NRNFG(810) are not used.
Users are not encouraged to change these values, as the
defaults are quite reasonable.
NPFLG = An array of 10 switches to produce debug printout.
There is a one to one correspondance to NRNFG, set
to 1 for output. (default = 0,0,0,0,0,0,0,0,0,0)
The most interesting is NPFLG(2)=1 to see the
transformed 1e integrals, NPFLG(2)=2 adds the
very numerous transformed 2e integrals to this.
IREST = n Restart the CI at stage NRNFG(n).
==========================================================
==========================================================
$DET group (required by MCSCF if CISTEP=ALDET or ORMAS)
$GEN group (required by MCSCF if CISTEP=GENCI)
$CIDET group (required if CITYP=ALDET, ORMAS, or FSOCI)
$CIGEN group (required if CITYP=GENCI)
This group describes the determinants to be used in a
MCSCF or CI wavefunction:
a) For full CI calculations (ALDET) the $DET/$CIDET
will generate a full list of determinants. If the CI is
part of an MCSCF, this means the MCSCF is of the FORS type
(which is also known as CASSCF).
b) For Occupation Restricted Multiple Active Space
(ORMAS) CI, the input in $ORMAS will partition the active
orbitals defined here into separate spaces, that is,
provide both $DET/$CIDET and $ORMAS.
c) For Full Second Order CI, provide $CIDET and $SODET
inputs.
d) For a general CI (meaning user specified space orbital
products) provide $DET/$CIDET plus $GEN/$CIGEN and most
likely $GCILST (according to the keyword GLIST).
In the above, group names for MCSCF/CI jobs are separated
by a slash.
Determinants contain several spin states, in contrast
to configuration state functions. The Sz quantum number
of each determinant is the same, but the Hamiltonian
eigenvectors will have various spins S=Sz, Sz+1, Sz+2, ...
so NSTATE may need to account for states of higher spin
symmetry. In Abelian groups, you can specify the exact
spatial symmetry you desire.
GLIST = general determinant list option
The keyword GLIST must not be given in a $DET or
$CIDET input group! These both generate full
determinant lists, automatically.
= INPUT means an input $GCILST group will be read.
= EXTRNL means the list will be read from a disk
file GCILIST generated in an earlier run.
= SACAS requests generation of sevaral CAS spaces
of different space symmetries, specified by
the input IRREPS. This option is intended
for state averaged calculations for cases
of high symmetry, where degenerate irreps
of the true group may fall into different
irreps of the Abelian subgroup used.
* * * The next four define the orbital spaces * * *
There is no default for NCORE, NACT, and NELS:
NCORE = total number of orbitals doubly occupied in all
determinants.
NACT = total number of active orbitals.
NELS = total number of active electrons.
SZ = azimuthal spin quantum number for each of the
determinants, two times SZ is therefore the
number of excess alpha spins in each determinant.
The default is SZ=S, extracted from the MULT=2S+1
given in $CONTRL.
* * * The following determine the state symmetry * * *
GROUP = name of the point group. The default is to copy
this from $DATA, if that group is Abelian (C2,
Ci, Cs, C2v, C2h, D2, or D2h). If not, the
group is set to C1 (no symmetry used).
ISTSYM = specifies the spatial symmetry of the state.
This table is exactly the same as in $DRT input.
ISTSYM= 1 2 3 4 5 6 7 8
C1 A
Ci Ag Au
Cs A' A''
C2 A B
C2v A1 A2 B1 B2
C2h Ag Bu Bg Au
D2 A B1 B2 B3
D2h Ag B1g B2g B3g Au B1u B2u B3u
Default is ISTSYM=1, the totally symmetric state.
IRREPS = specifies the symmetries of the GLIST=SACAS space
determinant list. This variable should always be
an array, as a single symmetry is more quickly
obtained by the regular full CI code. The values
given have the same meaning as the ISTSYM table.
* * * the following control the diagonalization * * *
NSTATE = Number of CI states to be found, the default is
1. The maximum number of states is 100.
PRTTOL = Printout tolerance for CI coefficients, the
default is to print any larger than 0.05.
ANALYS = a flag to request analysis of the CI energy in
terms of single and double excitation pair
correlation energies. This is normally used in
CI computations, rather than MCSCF, and when the
wavefunction is dominated by a single reference,
as the analysis is done in terms of excitations
from the determinant with largest CI coefficient.
The defalt is .FALSE.
ITERMX = Maximum number of Davidson iterations per root.
The default is 100. A CI calculation will fail
if convergence is not obtained before reaching
the limit. MCSCF computations will not bomb
if the iteration limit is reached, instead the
last CI vector is used to proceed into the next
orbital update. In cases with very large active
spaces, it may be faster to input ITERMX=2 or 3
to allow the program to avoid fully converging
the CI eigenvalue problem during the early MCSCF
iterations. For small active spaces, it is
best to allow the CI step to be fully converged
on every iteration.
CVGTOL = Convergence criterion for Davidson eigenvector
routine. This value is proportional to the
accuracy of the coeficients of the eigenvectors
found. The energy accuracy is proportional to
its square. The default is 1.0E5, but 1E6 if
gradients, MPLEVL, CITYP, or FMO selected).
NHGSS = dimension of the Hamiltonian submatrix which
is diagonalized to obtain the initial guess
eigenvectors. The determinants forming the
submatrix are chosen on the basis of a low
diagonal energy, or if needed to complete a
spin eigenfunction. The default is 300.
NSTGSS = Number of eigenvectors from the initial guess
Hamiltonian to be included in the Davidson's
iterative scheme. It is seldom necessary to
include extra states to obtain convergence to
the desired states. The default equals NSTATE.
MXXPAN = Maximum number of expansion basis vectors in the
iterative subspace during the Davidson iterations
before the expansion basis is truncated. The
default is the larger of 10 or 2*NSTGSS. Larger
values might help convergence, do not decrease
this parameter below 2*NSTGSS.
CLOBBR = a flag to erase the disk file containing CI
vectors from the previous MCSCF iteration. The
default is to use these as starting values for
the current iteration's CI. If you experience
loss of spin symmetry in the CI step, reverse
the default, to always take the CI from the top.
Default = .FALSE.
* * * the following control the 1st order density * * *
These are ignored during MCSCF, but are used during a CI.
IROOT = the root whose density is saved on the disk file
for subsequent property analysis. Only one root
can be saved, and the default value of 1 means
the ground state. Be sure to set NFLGDM to form
the density of the state you are interested in!
IROOT has a similar meaning for MCSCF, see below.
NFLGDM = Controls each state's density formation.
0 > do not form density for this state.
1 > form density and natural orbitals for this
state, print and punch occ.nums. and NOs.
2 > same as 1, plus print density over MOs.
The default is NFLGDM(1)=1,0,0,...,0 meaning
only ground state NOs are generated.
* * * the following control the state averaged
* * * 1st and 2nd order density matrix computation
Usually ignored by CI runs, these are relevant to MCSCF.
PURES = a flag controlling the spin purity of the state
avaraging. If true, the WSTATE array pertains
to the lowest states of the same S value as is
given by the MULT keyword in $CONTRL. In this
case the value of NSTATE will need to be bigger
than the total number of weights given by WSTATE
if there are other spin states present at low
energies. If false, it is possible to state
average over more than one S value, which might
be of interest in spinorbit coupling jobs.
The default is .TRUE.
WSTATE = An array of up to 100 weights to be given to the
densities of each state in forming the average.
The default is to optimize a pure ground state,
WSTATE(1)=1.0,0.0,...,0.0
A small amount of the ground state can help the
convergence of excited states greatly.
Gradient runs are possible only with pure states.
Be sure to set NSTATE above appropriately!
IROOT = the MCSCF state whose energy will be used as the
desired value. The default means to use the
average (according to WSTATE) of all states as
the FINAL energy, which of course is not a
physically meaningful quantity. This is mostly
useful for the numerical gradient of a specific
state obtained with state averaged orbitals.
(default=0).
IROOT has a similar meaning for CI, see above.
==========================================================
==========================================================
$ORMAS group (required by MCSCF if CISTEP=ORMAS)
(required for CITYP=ORMAS)
This group partitions an active space, defined in $DET
or $CIDET, into Occupation Restricted Multiple Active
Spaces (ORMAS). All possible determinants satisfying the
occupation restrictions (and of course the space symmetry
restriction given in $DET/$CIDET) will be generated. This
group's usefulness lies in reducing the large number of
determinants present in full CI calculations with large
active spaces.
There are no sensible defaults for these inputs, but
if the group is entirely omitted, a full CI calculation
will be performed. That is, the defaults are
NSPACE=1, MSTART(1)=NCORE+1, MINE(1)=NELS, MAXE(1)=NELS
meaning all active orbitals are in one partition.
NSPACE = number of orbital groups you wish to partition
the active space (NACT in $DET/$CIDET) into.
MSTART = an array of NSPACE integers. These specify where
each orbital group starts in the full list. You
must not overlook the NCORE core orbitals in
computing MSTART values. Space I runs from
orbital MSTART(I) up to orbital MSTART(I+1)1,
or NACT+NCORE if I is the last space, I=NSPACE.
IMPORTANT !!!! Remember to make sure your orbitals have
been reordered to suit MSTART, using NORDER in $GUESS.
MINE = an array of NSPACE integers. These specify the
minimum numbers of electrons that must always
occupy the orbital groups. In other words,
MINE(I) is the minimum number of electrons that
can occupy space I in any of the determinants.
MAXE = an array of NSPACE integers. These specify the
maximum numbers of electrons that must always
occupy the orbital groups. In other words,
MAXE(I) is the maximum number of electrons that
can occupy space I in any of the determinants.
The number of active electrons is NELS in $DET or $CIDET,
and the program will check that MINE/MAXE values are
consistent with this total number.
QCORR = a flag to request Davidsonstyle +Q corrections.
If this is not sensible for your CI choice, the
program will not print this correction, anyway.
The default is .TRUE.
FDIRCT = a flag to choose storage in memory of some
intermediates. This is very large, and slower in
the case of many occupied orbitals, but helpful
with a smaller number of orbitals. Therefore the
default for this is .TRUE. for MCSCF runs, but
.FALSE. during CI computations.
*** See REFS.DOC for more information on using ORMAS ***
==========================================================
==========================================================
$GCILST group (required by MCSCF if CISTEP=GENCI)
(required if CITYP=GENCI)
This group defines space products to be used in the
general CI calculation, or in a MCSCF wavefunction. The
input is free format.
Line 1: NSPACE ISYM
The first line gives the total number of space products to
be entered in the second lines. The option ISYM can be
omitted, or given as 0, in which case the program will
verify that all space products typed in the second lines
indeed have the spatial symmetry defined by ISTSYM in the
$GEN or $CIGEN input groups. If ISYM is 1, the user is
indicating that more than one space symmetry is known to
be in the list, that this is intentional, and the program
should proceed with the calculation. This might be of use
in state averaging two representations in a group that has
more than two total representations, and therefore faster
than turning symmetry off completely by GROUP=C1. ISYM=2
has the same meaning but turns on additional printing.
Line 2 is repeated NSPACE times. Each line 2 contains NACT
integers, which must be 0, 1, or 2, and therefore tells the
occupation of each of the active orbitals in each space
product. An example input is:
$GEN GLIST=INPUT NELS=6 NACT=4 SZ=0.0 $END
$GCILST
5
2 2 2 0
2 1 2 1
2 0 2 2
2 2 0 2
0 2 2 2
$END
which generates 6 Ms=0 determinants, much less than the 16
determinants in a C1 symmetry full list for 6 e in 4 MOs.
The second space product above generates two determinants.
All space products with singly occupied orbitals are used
to form all possible determinants, to ensure that the final
states are eigenfunctions of the S**2 operator (meaning
they will be pure spin states).
Note that there is no way at present to generate lists
such as singles and doubles from a single reference.
Convergence of MCSCF calculations will depend on how well
chosen your determinant list is, and may very well require
the use of the FULLNR or JACOBI convergers.
==========================================================
==========================================================
$SODET group (required if CITYP=FSOCI)
This group controls a full second order CI calculation
using determinants (see also the keyword SOCI in $CIDRT).
Most of the characteristics of the active space (such as
NCORE, NACT, NELS) must be given in a $CIDET group, as
a preliminary full CI according to $CIDET will be made.
The FCI states will then used as the initial guess for
the full second order CI. A few additional parameters may
be given in this group, but many runs will not need to
give any of these.
NEXT = the number of external orbitals to be included.
The default is the entire virtual MO space.
NSOST = the number of states to be found in the SOCI.
The default is copied from NSTATE in $CIDET.
MAXPSO = maximum expansion space size used in the SOCI.
The default is copied from MXXPAN in $CIDET.
ORBS = MOS means use the MCSCF orbitals, which should be
allowed to undergo canonicalization (see the
CANONC keyword in $MCSCF), or the input $VEC
group in case SCFTYP=NONE. (default)
NOS means to instead use the natural orbitals of
the MCSCF.
==========================================================
==========================================================
$DRT group (required by MCSCF if CISTEP=GUGA)
$CIDRT group (required if CITYP=GUGA)
This group describes the Configuration State Functions
(CSFs) used by the MCSCF or CI calculation. The Distinct
Row Table (DRT) is the means by which the Graphical Unitary
Group Approach (GUGA) specifies configurations. The group
is spelled $DRT for MCSCF runs, and $CIDRT for CI runs.
The main difference in these is NMCC versus NFZC.
There is no default for GROUP, and you must choose one
of FORS, FOCI, SOCI, or IEXCIT.
GROUP = the name of the point group to be used. This is
usually the same as that in $DATA, except for
RUNTYP=HESSIAN, when it must be C1. Choose from
the following: C1, C2, CI, CS, C2V, C2H, D2, D2H,
C4V, D4, D4H. If your $DATA group is not listed,
choose only C1 here.
FORS = flag specifying the Full Optimized Reaction Space
set of configuration should be generated. This
is usually set true for MCSCF runs, but if it is
not, see FORS in $MCSCF. (Default=.FALSE.)
FOCI = flag specifying first order CI. In addition to
the FORS configurations, all singly excited CSFs
from the FORS reference are included.
Default=.FALSE.
SOCI = flag specifying second order CI. In addition to
the FORS configurations, all singly and doubly
excited configurations from the FORS reference
are included. (Default=.FALSE.)
IEXCIT= electron excitation level, for example 2 will
lead to a singles and doubles CI. This variable
is computed by the program if FORS, FOCI, or
SOCI is chosen, otherwise it must be entered.
INTACT= flag to select the interacting space option. See
C.F.Bender, H.F.Schaefer J.Chem.Phys. 55,
47984803(1971). The CI will include only those
CSFs which have nonvanishing spin couplings with
the reference configuration. Note that when the
Schaefer group uses this option for high spin
ROHF references, they use Guest/Saunders orbital
canonicalization.
* * the next variables define the single reference * *
The single configuration reference is defined by
filling in the orbitals by each type, in the order shown.
The default for each type is 0.
Core orbitals, which are always doubly occupied:
NMCC = number of MCSCF core MOs (in $DRT only).
NFZC = number of CI frozen core MOs (in $CIDRT only).
Internal orbitals, which are partially occupied:
NDOC = number of doubly occupied MOs in the reference.
NAOS = number of alpha occupied MOs in the reference,
which are singlet coupled with a corresponding
number of NBOS orbitals.
NBOS = number of beta spin singly occupied MOs.
NALP = number of alpha spin singly occupied MOs in the
reference, which are coupled high spin.
NVAL = number of empty MOs in the reference.
External orbitals, occupied only in FOCI or SOCI:
NEXT = number of external MOs. If given as 1, this will
be set to all remaining orbitals (apart from any
frozen virtual orbitals).
NFZV = number of frozen virtual MOs, never occupied.
* * the next two help with state symmetry * *
ISTSYM= irreducible representation for GUGA wavefunction.
This option overwrites whatever symmetry is implied
by NALP/NAOS/NBOS. Default=0 means ISTSYM will be
inferred from the symmetry of the reference, namely
from the symmetry of NALP/NAOS/NBOS orbitals.
ISTSYM= 1 2 3 4 5 6 7 8
C1 A
Ci Ag Au
Cs A' A''
C2 A B
C2v A1 A2 B1 B2
C2h Ag Bu Bg Au
D2 A B1 B2 B3
D2h Ag B1g B2g B3g Au B1u B2u B3u
It is no doubt easier to just select the desired
ISTSYM directly. Its computation from the singly
occupied orbitals is kept merely to preserve old
input files.
NOIRR= controls labelling of the CI state symmetries.
= 1 no labelling (default)
= 0 usual labelling. This can be very time consuming
if the group is nonAbelian.
=1 fast labelling, in which all CSFs with small CI
coefficients are ignored. This can produce weights
quite different from one, due to ignoring small
coefficients, but overall seems to work OK.
Note that it is normal for the weights not to sum
to 1 even for NOIRR=0 because for simplicity the
weight determination is focused on the relative
weights rather than absolute. However weight do
not sum to one only for rowmixed MOs.
= 2,3... fast labelling and sets SYMTOL=10**NOIRR
for runs other than TRANSITN. All irreps with
weights greater than SYMTOL are considered.
* * * the final choices are seldom used * * *
MXNINT = Buffer size for sorted integrals. (default=20000)
Adjust this upwards if the program tells you to,
which may occur in cases with large numbers of
external orbitals.
MXNEME = Buffer size for energy matrix. (default=10000)
NPRT = Configuration printout control switch.
This can consume a HUMUNGUS amount of paper!
0 = no print (default)
1 = print electron occupancies, one per line.
2 = print determinants in each CSF.
3 = print determinants in each CSF (for Ms=S1).
==========================================================
==========================================================
$MCSCF group (for SCFTYP=MCSCF)
This group controls the MCSCF orbital optimization
step. The difference between the five convergence methods
is outlined in the Further Information chapter, which you
should carefully study before trying MCSCF computations.
 the next chooses the configuration basis 
CISTEP = ALDET chooses the Ames Lab. determinant full CI,
and requires $DET input. (default)
= ORMAS chooses an Occupation Restricted Multiple
Active Space determinant CI, requiring
both $DET and $ORMAS inputs.
= GUGA chooses the graphical unitary group CSFs,
and requires $DRT input. This is the
only value usable with the QUAD converger.
= GENCI chooses the Ames Lab. general CI, and
requires $GEN input.
 the next five choose the orbital optimizer 
FOCAS = a flag to select a method with a first order
convergence rate. (default=.FALSE.)
Parallel runs with FOCAS do not use MEMDDI.
SOSCF = a flag selecting an approximately second order
convergence method, using an approximate orbital
hessian. (default=.TRUE.)
Parallel runs with SOSCF do not use MEMDDI.
FULLNR = a flag selecting a second order method, with an
exact orbital hessian. (default=.FALSE.)
Parallel runs with FULLNR require input of MEMDDI.
QUAD = a flag to pick a fully quadratic (orbital and
CI coefficient) optimization method, which is
applicable to FORS or nonFORS wavefunctions.
QUAD may not be used with stateaveraging.
(default = .FALSE.)
This converger can be used only in serial runs.
JACOBI = a flag to pick a program that minimizes the
MCSCF energy by a sequence of 2x2 Jacobi
orbital rotations. This is very systematic in
forcing convergence, although the number of
iterations may be high and the time longer
than the other procedures. This option does
not compute the orbital Lagrangian, hence at
present nuclear gradients may not be computed.
(default = .FALSE.)
This converger can be used only in serial runs.
Note that FOCAS must be used only with FORS=.TRUE. in $DRT.
The other convergers are usable for either FORS or nonFORS
wavefunctions, although convergence is always harder in the
latter case, when FORS below must be set .FALSE.
 the next apply to all convergence methods 
FORS = a flag to specify that the MCSCF function is of
the Full Optimized Reaction Space type, which is
sometimes known as CASSCF. .TRUE. means omit
activeactive rotations from the optimization.
Since convergence is usually better with these
rotations included, the default is sensible:
.TRUE. for FOCAS, .FALSE. for FULLNR or QUAD,
and for SOSCF, .TRUE. for ALDET/GUGA but .FALSE.
for ORMAS/GENCI)
ACURCY = the major convergence criterion, the maximum
permissible asymmetry in the Lagrangian matrix.
(default=1E5, but 1E6 if MPLEVL, CI, or FMO
is selected.)
ENGTOL = a secondary convergence criterion, the run is
considered converged when the energy change is
smaller than this value. (default=1.0E10)
MAXIT = Maximum number of iterations (default=100 for
FOCAS, 60 for SOSCF, 30 for FULLNR or QUAD)
MICIT = Maximum number of microiterations within a
single MCSCF iteration. (default=5 for FOCAS
or SOSCF, or 1 for FULLNR or QUAD)
NWORD = The maximum memory to be used, the default is
to use all available memory. (default=0)
CANONC = a flag to cause formation of the closed shell
Fock operator, and generation of canonical core
orbitals. This will order the MCC core by their
orbital energies. (default=.TRUE.)
EKT = a flag to cause generation of extended Koopmans'
theorem orbitals and energies. (Default=.FALSE.)
For this option, see R.C.Morrison and G.Liu,
J.Comput.Chem., 13, 10041010 (1992). Note that
the process generates nonorthogonal orbitals, as
well as physically unrealistic energies for the
weakly occupied MCSCF orbitals. The method is
meant to produce a good value for the first I.P.
NPUNCH = MCSCF punch option (analogous to $SCF NPUNCH)
0 do not punch out the final orbitals
1 punch out the occupied orbitals
2 punch out occupied and virtual orbitals
The default is NPUNCH = 2.
NPFLG = an array of debug print control. This is
analagous to the same variable in $CIINP.
Elements 1,2,3,4,6,8 make sense, the latter
controls debugging the orbital optimization.
 the next refers to SOSCF optimizations 
NOFO = number of FOCAS iterations before switching to the
SOSCF converger. May be 0, 1, ... (default=1).
One FOCAS iteration at the first geometry permits
a canonicalization of the virtual space to occur,
which is likely to be crucial for convergence.
MCFMO = set to 1 to remove redandant orbital Lagrangian
elements in FMOMCSCF. Note that corresponding
orbital rotations will still be optimised but not
considered when deciding whether a run converged.
This option is only in effect if fractioned bonds
are present (for which redundant orbitals exist).
Default: 1.
(This variable is irrelevant except to FMO runs)
 the next three refer to FOCAS optimizations 
CASDII = threshold to start DIIS (default=0.05)
CASHFT = level shift value (default=1.0)
NRMCAS = renormalization flag, 1 means do Fock matrix
renormalization, 0 skips (default=1)
 the next applies to the QUAD method 
(note that all FULLNR input is also relevant to QUAD)
QUDTHR = threshold on the orbital rotation parameter,
SQCDF, to switch from the initial FULLNR
iterations to the fully quadratic method.
(default = 0.05)
 The JACOBI converger accepts FULLNR options 
 NORB, NOROT, MOFRZ, and FCORE as input 
 all remaining input applies only to FULLNR 
DAMP = damping factor, this is adjusted by the program
as necessary. (default=0.0)
METHOD = DM2 selects a density driven construction of the
NewtonRaphson matrices. (default).
= TEI selects 2e integral driven NR construction.
See the 'further information' section for more
details concerning these methods. TEI is slow!
LINSER = a flag to activate a method similar to direct
minimization of SCF. The method is used if
the energy rises between iterations. It may in
some circumstances increase the chance of
converging excited states. (default=.FALSE.)
FCORE = a flag to freeze optimization of the MCC core
orbitals, which is useful in preparation for
RUNTYP=TRANSITN jobs. Setting this flag will
automatically force CANONC false. This option
is incompatible with gradients, so can only be
used with RUNTYP=ENERGY. It is a good idea to
decrease TOLZ and TOLE in $GUESS by two orders
of magnitude to ensure the core orbitals are
unchanged during input. (default=.FALSE.)
 the last four FULLNR options are seldom used 
DROPC = a flag to include MCC core orbitals during the
CI computation. The default is to drop them
during the CI, instead forming Fock operators
which are used to build the correct terms in
the orbital hessian. (default = .TRUE.)
NORB = the number of orbitals to be included in the
optimization, the default is to optimize with
respect to the entire basis. This option is
incompatible with gradients, so can only be used
with RUNTYP=ENERGY. (default=number of AOs
given in $DATA).
MOFRZ = an array of orbitals to be frozen out of the
orbital optimization step (default=none frozen).
NOROT = an array of up to 250 pairs of orbital rotations
to be omitted from the NR optimization process.
The program automatically deletes all corecore
rotations, all actact rotations if FORS=.T.,
and all coreact and corevirt rotations if
FCORE=.T. Additional rotations are input as
I1,J1,I2,J2... to exclude rotations between
orbital I running from 1 to NORB, and J running
up to the smaller of I or NVAL in $TRANS.
==========================================================
==========================================================
$MRMP group (relevant if SCFTYP=MCSCF, MPLEVL=2)
This group allows you to specify which multireference
perturbation program is executed. At the present time, the
determinant and CSF programs produce identical results, so
the choice is largely one of computer efficiency.
MRPT = DETPT requests a determinant program. The MCSCF
computation must use CISTEP=ALDECI, as this
program inherits orbital spaces, and state
selection options only from $DET.
See $DETPT for related input.
(default for most runs)
= MCQDPT requests a CSF (GUGA based) program. This
is the only program that can do spinorbit
MRPT, apply energy denominators in case of
socalled "intruder states", or find the
weight of the MCQDPT zeroth order state.
CISTEP can be ALDECI or GUGA, your choice.
See $MCQDPT for related input.
(default for RUNTYP=TRANSITN)
These two programs produce numerically identical results,
if you select a tight value of THRGEN=1D12 for the latter
program (in some cases you may also need to tighten the CI
convergence criteria). Eight or more decimal place energy
agreement between the two codes has been observed, when
being careful about these cutoffs. This is true whether
the codes are running in single state mode, which the
literature calls MRMP, or in multistate mode, which the
literature calls MCQDPT.
Generally speaking, the determinant code uses direct CI
technology to avoid disk I/O, and is much faster when used
with larger active spaces (particularly above 12 active
orbitals). The determinant code uses essentially no disk
space beyond that required by the MCSCF itself. The
determinant code uses native integral transformation codes,
including the distributed memory parallel transformation.
However, the determinant code is perhaps a bit slower when
there is a small active space and very many filled valence
orbitals included in the PT. Both codes exploit
distributed memory parallelization.
The determinant program is relatively new, and still lacks
complete control of state weights and canonicalization. Be
careful to read in only canonicalized core, active, and
virtual MOs if you pick RDVECS=.TRUE. with this program.
If you have any doubts about transitioning to the
determinant code, please try running a calculation both
ways, checking that you get the same results.
Please note that the CASPT2 equations are not implemented
in GAMESS, and thus your runs should be described as being
MRMP/MCQDPT in any publications. See REFS.DOC for more
details about different multireference PTs.
RDVECS = a flag controlling whether the orbitals should be
MCSCF optimized in this run. A value of .TRUE.
means that your converged MCSCF orbitals are being
given in $VEC, and the program will branch to the
perturbation treatement. If you are using the
determinant program, $GUESS is read and its
options apply to reading the $VEC group. If you
are using the CSF program, $GUESS is ignored, and
the $VEC or $VECn group must contain all virtuals.
(default=.FALSE.)
==========================================================
==========================================================
$DETPT group (relevant if SCFTYP=MCSCF and MPLEVL=2)
This input group applies to the determinantbased
multireference perturbation theory program, if chosen by
MRPT=DETPT in $MRMP group.
When applied to only one state, the theory is known as
multireference MollerPlesset (MRMP), but the term MCQDPT
is used when this theory is used in its multistate form.
Please note that this perturbation theory is not the same
thing as the CASPT2 theory, and should NEVER be called
that. A more complete discussion may be found in the
'Further Information' chapter.
NVAL = number of filled valence orbitals in the MCSCF to
be included in the dynamic correlation treatment.
This is analogous to NMODOC in the $MCQDPT group.
The number of frozen cores orbitals is found by
subtracting NVAL from NCORE in $DET, so that you
need not specify the chemical core's size. Also,
there is no input for specifying the active space,
which is inherited from $DET. The default for
NVAL correlates valence orbitals, but freezes any
chemical cores.
NEXT = number of external orbitals to use. The default
means to use all of them (default=1).
NOS = a flag to use MCSCF natural orbitals rather than
canonicalized orbitals as the basis of the PT.
This changes the numerical results!!!
Omitting NPTST, IPTST, and WPTST is the simplest option,
meaning that any state with a nonzero WSTATE in $DET is
included in the pertubation. Canonicalization of the
orbitals is normally done by the MCSCF program, see CANONC
in $MCSCF. However, if not, or if the state weights are
changed, the canonicalization is done in the perturbation
code, according to CANON in this group. The default is the
most computationally efficient.
CANON = flag to request canonicalization. Default=.TRUE.
Turning off canonicalization is for experimental
purposes, so most runs should not avoid it. The
canonicalization will be done in the perturbation
code under three circumstances,
RDVECS=.TRUE. was used, at the first geometry,
the MCSCF step skipped canonicalization, or
you enter NPTST/IPTST/SPTST information.
Canonicalization uses the state averaged density
matrix to build the "standard Fock operator", and
involves diagonalizing its diagonal subblocks.
NPTST = the number of states to include in generation of
the unperturbed CAS states. If NPTST is chosen,
spins of the states will be ignored, like using
PURES=.F. in $DET, so you must be careful in your
matching IPTST input.
IPTST = an array of CASCI states to be included in the
perturbation theory, give NPTST values.
WPTST = an array of state weights. Like NPTST/WPTST, the
default is derived from WSTATE in $DET.
example: NPTST=3 IPTST(1)=1,3,5 might be used to include
three singlets, S0,S1,S2 in a MCQDPTtype treatment, but
skip over T1 and T2. You will have done an earlier CI or
MCSCF run, in order to know that you need NPTST five or
higher to capture the lowest three singlets, and that these
singlets appear where they do. NSTATE in $DET must be at
least 5 in this example, to find enough roots.
==========================================================
==========================================================
$MCQDPT group (relevant if SCFTYP=MCSCF and MPLEVL=2)
Controls 2nd order MCQDPT (multiconfiguration quasi
degenerate perturbation theory) runs, if requested by
MPLEVL=2 in $CONTRL. MCQDPT2 is implemented only for FORS
(aka CASSCF) wavefunctions. The MCQDPT method is a
multistate, as well as multireference perturbation theory.
The implementation is a separate program, interfaced to
GAMESS, with its own procedures for determination of the
canonical MOs, CSF generation, integral transformation, CI
in the reference CAS, etc. Therefore some of the input in
this group repeats data given elsewhere, particularly for
$DET/$DRT.
Analytic gradients are not available. Spinorbit
coupling may be treated as a perturbation, included at the
same time as the energy perturbation. If spinorbit
calculations are performed, the input groups for each
multiplicity are named $MCQD1, $MCQD2, ... rather than
$MCQDPT. Parallel calculation is enabled.
When applied to only one state, the theory is known as
multireference MollerPlesset (MRMP), but the term MCQDPT
is used when this theory is used in its multistate form.
Please note that this perturbation theory is not the same
thing as the CASPT2 theory, and should NEVER be called
that. A more complete discussion may be found in the
'Further Information' chapter.
*** MCSCF reference wavefunction ***
NEL = total number of electrons, including core.
(default from $DATA and ICHARG in $CONTRL)
MULT = spin multiplicity (default from $CONTRL)
NMOACT = Number of orbitals in FORS active space
(default is the active space in $DET or $DRT)
NMOFZC = number of frozen core orbitals, NOT correlated
in the perturbation calculation. (default is
number of chemical cores)
NMODOC = number of orbitals which are doubly occupied in
every MCSCF configuration, that is, not active
orbitals, which are to be included in the
perturbation calculation. (The default is all
valence orbitals between the chemical core and
the active space)
NMOFZV = number of frozen virtuals, NOT occupied during
the perturbation calculation. The default is
to use all virtuals in the MP2. (default=0)
If the input file does not provide a $DET or $DRT, the user
must give NMOFZC, NMODOC, and NMOACT correctly here.
ISTSYM = the state symmetry of the target state(s).
This is given as an integer, note that only
Abelian groups in $DATA are supported:
ISTSYM= 1 2 3 4 5 6 7 8
C1 A
Ci Ag Au
Cs A' A''
C2 A B
C2v A1 A2 B1 B2
C2h Ag Bu Bg Au
D2 A B1 B2 B3
D2h Ag B1g B2g B3g Au B1u B2u B3u
(The default is inherited from $DET or $DRT)
NOSYM = 0 use CSF symmetry (see the ISTSYM keyword).
off diagonal perturbations vanish if states are
of different symmetry, so the most efficient
computation is a separate run for every space
symmetry. (default)
1 turn off CSF state symmetry so that all states
are treated at once. ISTSYM is ignored.
Presently this option does not seem to work!!
1 Symmetry purify the orbitals. Since $GUESS is
not read by MCQDPT runs, this option can be used
as a substitute for its PURIFY. After cleaning
the orbitals, they are reorthogonalised within
each irrep and within each group (core, double,
active, virtual) separately. Since this occurs
without MCSCF optimization if you have chosen to
use RDVECS in $MRMP, it is *your* responsibility
to ensure that any purification of the orbitals
is small enough that the CAS energies for the
original CASSCF and the CASCI performed during
the MCQDPT are the same!
*** perturbation specification ***
KSTATE= state is used (1) or not (0) in the MCQDPT2.
Maximum of 20 elements, including zeros.
For example, if you want the perturbation
correction to the second and the fourth roots,
KSTATE(1)=0,1,0,1
See also WSTATE. (default=1,0,0,0,0,0,0,...)
*** Intruder State Removal ***
EDSHFT = energy denominator shifts. (default=0.0,0.0)
See also REFWGT.
Intruder State Avoidance (ISA) calculations can be made by
changing the energy denominators around poles (where the
denominator is zero). Each denominator x is replaced by x
+ EDSHFT/x, so that far from the poles (when x is large)
the effect of such change is small. EDSHFT is an array of
two values, the first is used in spinfree MCQDPT, and the
second is for spinorbit MCQDPT. Both values are used if
RUNTYP=TRNSTN, only the first is used otherwise. A
suggested pair of values is 0.02,0.1, but experimentation
with your system is recommended. Setting these values to
zero is ordinary MCQDPT, whereas infinite collapses to the
MCSCF reference.
Note that the energy denominators (which are ketdependent
in MCQDPT) are changed in a different way for each ket
vector, that is, for each row in MCQDPT Hamiltonian matrix.
In other words, the zeroth order energies are not
"universal", but state specific. This is strictly speaking
an inconsistency in defining zeroth order energies that are
usually chosen "universally".
In order to maintain continuity when studying a PES, one
usually uses the same EDSHFT values for all points on PES.
In order to study the potential surface for any extended
range of geometries, it is recommended to use ISA, as it is
quite likely that one or more regions of the PES will be
unphysical due to intruder states.
For an example of how intruder states can appear at some
points on the PES, see Figures 1,2,7 of
K.R.Glaesemann, M.S.Gordon, H.Nakano
Phys.Chem.Chem.Phys. 1, 967975(1999)
and also
H.A.Witek, D.G.Fedorov, K.Hirao, A.Viel, P.O.Widmark
J.Chem.Phys. 116, 8396406(2002)
For a discussion of intruder state removal from MCQDPT, see
H.A.Witek, Y.K.Choe, J.P.Finley, K.Hirao
J.Comput.Chem. 23, 957965(2002)
REFWGT = a flag to request decomposition of the second
order energy into internal, semiinternal, and
external contributions, and to obtain the weight
of the MCSCF reference in the 1st order wave
function. This option significantly increases
the run time! When you run in parallel, only
the transformation steps will speed up, as the
PT part of the reference weight calculation has
not been adapted for speedups (default=.FALSE.)
The EDSHFT option does not apply if REFWGT is
used. One purpose of using REFWGT is to try to
understand the nature of the intruder states.
*** Canonical Fock orbitals ***
IFORB = 0 omit this step.
= 1 determine the canonical Fock orbitals. (default)
= 3 canonicalise the Fock orbitals averaged over
all $MCQDx input groups.
This option pertains only to RUNTYP=TRANSITN. It is
primarily meant to include spinorbit coupling perturbation
into the energy perturbation, but could also be used in
conjunction with OPERAT=DM to calculate only the second
order energy perturbation. IFORB=3 means that WSTATE is
used as follows: In each $MCQDx group, the WSTATE weights
are divided by the total number of states (sum(i)
IROOTS(i)), so the sum over all WSTATE values in all $MCQDx
groups is normalized to sum to 1. Thus there is no
normalization to 1 within each $MCQDx group.
This option might be used to speed up an atomic MCQDPT,
e.g. if computing the 3P ground state of carbon, one would
want to average over all three spatial components of the P
term, to be sure of spatial degeneracy, but then run the
perturbation using symmetry, separately on the B1g+B2g+B3g
subspecies (within D2h) of a P term. It is very important
to give weights appropriate for the symmetry, the input
requires care.
WSTATE = weight of each CASCI state in computing the
closed shell Fock matrix. You must enter 0.0
whenever the same element in KSTATE is 0.
In most cases setting the WSTATEs for states
to be included in the MCQDPT to equal weights
is the best, and this is the default.
*** Miscellaneous options ***
ISELCT is an option to select only the important CSFs
for inclusion into the CASCI reference states.
Set to 1 to select, or 0 to avoid selection of
CSFs (default = 0)
All CSFs in a preliminary complete active space
CI whose CI coefficients exceed the square root
of THRWGT are kept in a smaller CI to determine
the zeroth order states. Note that the CSFs
with smaller coefficients, while excluded from
the reference states, are still used during the
perturbation calculation, so most of their
energy contribution is still retained. This can
save appreciable computer time in cases with
large active spaces.
THRWGT = weight threshold for retaining CSFs in selected
configuration runs. In quantum mechanics, the
weight of a CSF is the square of its CI
coefficient. (default=1d6)
THRGEN = threshold for one, two, and threebody
density matrix elements in the perturbation
calculation. The default gives about 5 decimal
place accuracy in energies. Increase to 1.0D12
if you wish to obtain higher accuracy, for
example, in numerical gradients (default=1D8).
Tightening THRGRN and perhaps CI diagonalization
should allow 78 decimal place agreement with
the determinant code.
THRENE = threshold for the energy convergence in the
Davidson's method CASCI. (default=1.0D+00)
THRCON = threshold for the vector convergence in the
Davidson's method CASCI. (default=1.0D06)
MDI = dimension of small Hamiltonian diagonalized to
prepare initial guess CI states. (default=50)
MXBASE = maximum number of expansion vectors in the
Davidson diagonalization subspace (e.g. MXXPAN).
(default=50)
NSOLUT = number of states to be solved for in the
Davidson's method, this might need to exceed
the number of states in the perturbation
treatment in order to "capture" the correct
roots.
NSTOP = maximum number of iterations to permit in
the Davidson's diagonalization.
LPOUT = print option, 0 gives normal printout, while
<0 gives debug print (e.g. 1, 5, 10, 100)
In particular, LPOUT=1 gives more detailed
timing information. (default=0)
The next three parameters refer to parallel execution:
DOORD0 = a flag to select reordering of AO integrals
which speeds the integral transformations.
This reduces disk writes, but increases disk
reads, so you can try turning it off if your
machine has slow writes. (default=.TRUE.)
PARAIO = access 2e integral file on every node, at
the same time. This affects only runs with
DOORD0 true, and it may be useful to turn
this off in the case of SMP nodes sharing
a common disk drive. (default=.TRUE.)
DELSCR = a flag to delete file 56 containing half
transformed integrals after it has been
used. This reduces total disk requirements
if this file is big. (default=.FALSE.)
Note that parallel execution will be more effective if you
use distributed memory, MEMDDI in $SYSTEM. Using
AOINTS=DIST in $TRANS is likely to be helpful in situations
with relatively poor I/O rates compared to communication,
e.g. SMP enclosures forced to share a single scratch disk
system. See PROG.DOC for more information on parallel
execution.
Finally, there are additional very specialized options,
described in the source code routine MQREAD: IROT, LENGTH,
MAXCSF, MAXERI, MAXROW, MXTRFR, THRERI, MAINCS, NSTATE
==========================================================
The input groups $CISORT, $GUGEM, $GUGDIA, $GUGDM, $GUGDM2,
$LAGRAN, and $TRFDM2 pertain only to GUGA CI, chosen by
either CITYP=GUGA or CISTEP=GUGA. The most important of
these values may be given for determinant runs (using the
same keyword spellings) in the $DET group.
==========================================================
$CISORT group (relevant for GUGA CI or MCSCF)
This group provides further control over the sorting
of the transformed molecular integrals into the order the
GUGA program requires.
NDAR = Number of direct access records.
(default = 2000)
LDAR = Length of direct access record (site dependent)
NBOXMX = Maximum number of boxes in the sort.
(default = 200)
NWORD = Number of words of fast memory to use in this
step. A value of 0 results in automatic use of
all available memory. (default = 0)
NOMEM = 0 (set to one to force out of memory algorithm)
==========================================================
$GUGEM group (relevant for GUGA CI or MCSCF)
This group provides further control over the
calculation of the energy (Hamiltonian) matrix.
CUTOFF = Cutoff criterion for the energy matrix.
(default=1.0E8)
NWORD = not used.
==========================================================
==========================================================
$GUGDIA group (relevant for GUGA CI or MCSCF)
This group provides control over the Davidson method
diagonalization step.
NSTATE = Number of CI states to be found. (default=1)
You can solve for any number of states, but only
100 can be saved for subsequent sections, such
as state averaging.
PRTTOL = Printout tolerance for CI coefficients
(default = 0.05)
MXXPAN = Maximum no. of expansion basis vectors used
before the expansion basis is truncated.
(default=30)
ITERMX = Maximum number of iterations (default=50)
CVGTOL = Convergence criterion for Davidson eigenvector
routine. This value is proportional to the
accuracy of the coeficients of the eigenvector(s)
found. The energy accuracy is proportional to
its square. (default=1.0d5, but 1E6 if
gradients, MPLEVL, CITYP, or FMO selected).
NWORD = Number of words of fast memory to use in this
step. A value of zero results in the use of all
available memory. (default = 0)
MAXHAM = specifies dimension of Hamiltonian to try to
store in memory. The default is to use all
remaining memory to store this matrix in memory,
if it fits, to reduce disk I/O to a minimum.
MAXDIA = maximum dimension of Hamiltonian to send to an
incore diagonalization. If the number of CSFs
is bigger than MAXDIA, an iterative Davidson
procedure is invoked. Default=100
NIMPRV = Maximum no. of eigenvectors to be improved every
iteration. (default = nstate)
NSELCT = Determines initial guess to eigenvectors.
= 0 > Unit vectors corresponding to the NSTATE
lowest diagonal elements and any diagonal
elements within SELTHR of them. (default)
< 0 > First abs(NSELCT) unit vectors.
> 0 > use NSELCT unit vectors corresponding to
the NSELCT lowest diagonal elements.
SELTHR = Guess selection threshold when NSELCT=0.
(default=0.01)
NEXTRA = Number of extra expansion basis vectors to be
included on the first iteration. NEXTRA is
decremented by one each iteration. This may be
useful in "capturing" vectors for higher states.
(default=5)
On AXP processors, enter as 0 to avoid core dumps.
KPRINT = Print flag bit vector used when
NPFLG(4)=1 in the $CIINP group (default=8)
value 1 bit 0 print final eigenvalues
value 2 bit 1 print final tolerances
value 4 bit 2 print eigenvalues and tolerances
at each truncation
value 8 bit 3 print eigenvalues every iteration
value 16 bit 4 print tolerances every iteration
Inputs for a multireference Davidson correction, in case
the orbitals are from a MCSCF.
NREF = number of CSFs in the MCSCF (full CI) job.
EREF = the energy of the MCSCF reference.
==========================================================
==========================================================
$GUGDM group (relevant for GUGA CI)
This group provides further control over formation of
the one electron density matrix. See NSTATE in $GUGDIA.
NFLGDM = Controls each state's density formation.
0 > do not form density for this state.
1 > form density and natural orbitals for this
state, print and punch occ.nums. and NOs.
2 > same as 1, plus print density over MOs.
(default=1,99*0, means ground state NOs only)
Note that forming the 1particle density for a state is
negligible compared to diagonalization time for that state.
IROOT = The root whose density matrix is saved on desk for
later computation of properties. You may save
only one state's density per run, by default, this
is the ground state (default=1).
WSTATE = An array of up to 100 weights to be given to the
1 body density of each state. The averaged density
will be used for property computations, as well as
"state averaged natural orbitals". The default is
to use NFLGDM/IROOT, unless WSTATE is given, when
NFLGDM/IROOT are ignored.
It is not physically reasonable to average over
any CI states that are not degenerate, but it
may be useful to use WSTATE to produce a totally
symmetric density when the states are degenerate.
IBLOCK = Density blocking switch. If nonzero, the off
diagonal block of the density above row IBLOCK
will be set to zero before the (now approximate)
natural orbitals are found. One use for this is
to keep the internal and external orbitals in a
FOCI or SOCI calculation from mixing, where IBLOCK
is the highest internal orbital. (default=0)
NWORD = Number of words of memory to use. Zero means use
all available memory (default=0).
==========================================================
==========================================================
$GUGDM2 group (relevant for GUGA CI or MCSCF)
This group provides control over formation of the
2particle density matrix.
WSTATE = An array of up to 100 weights to be given to the
2 body density of each state in forming the DM2.
The default is to optimize a pure ground state.
(Default=1.0,99*0.0)
A small amount of the ground state can help the
convergence of excited states greatly.
Gradient runs are possible only with pure states.
IROOT = the MCSCF state whose energy will be used as the
desired value. The default means to use the
average (according to WSTATE) of all states as
the FINAL energy, which of course is not a
physically meaningful quantity. This is mostly
useful for the numerical gradient of a specific
state obtained with state averaged orbitals.
(default=0).
Be sure to set NSTATE in $GUGDIA appropriately!
CUTOFF = Cutoff criterion for the 2ndorder density.
(default = 1.0E9)
NWORD = Number of words of fast memory to use in sorting
the DM2. The default uses all available memory.
(default=0).
NOMEM = 0 uses in memory sort, if possible.
= 1 forces out of memory sort.
NDAR = Number of direct access records. (default=4000)
LDAR = Length of direct access record (site dependent)
NBOXMX = Maximum no. of boxes in the sort. (default=200)
==========================================================
==========================================================
$LAGRAN group (relevant for GUGA CI gradient)
This group provides further control over formation of
the CI Lagrangian, a quantity which is necessary for the
computation of CI gradients.
NOMEM = 0 form in core, if possible
= 1 forces out of core formation
NWORD = 0 (0=use all available memory)
NDAR = 4000
LDAR = Length of each direct access record
(default is NINTMX from $INTGRL)
==========================================================
==========================================================
$TRFDM2 group (relevant for GUGA CI gradient)
This group provides further control over the back
transformation of the 2 body density to the AO basis.
NOMEM = 0 transform and sort in core, if possible
= 1 transform in core, sort out of core, if poss.
= 2 transform out of core, sort out of core
NWORD = 0 (0=use all available memory)
CUTOFF= 1.0D9, threshold for saving DM2 values
NDAR = 2000
LDAR = Length of each direct access record
(default is system dependent)
NBOXMX= 200
==========================================================
Usually neither $LAGRAN or $TRFDM2 group are given. Since
these groups are normally used only for CI gradient runs,
we list here the restrictions on the GUGA CI gradients:
a) SCFTYP=RHF, only
b) no FZV orbitals in $CIDRT, all MOs must be used.
c) the derivative integrals are computed in the 2nd
derivative code, which is limited to spd basis sets.
d) the code does not run in parallel.
e) Use WSTATE in $GUGDM2 to specify the state whose
gradient is to be found. Use IROOT in $GUGDM to
specify the state whose other properties will be
found. These must be the same state!
f) excited states often have different symmetry than the
ground state, so think about GROUP in $CIDRT.
g) the gradient can probably be found for any CI for
which you have sufficient disk to do the CI itself.
Time is probably about 2/3 additional.
See also $CISGRD for CI singles gradients.
==========================================================
$TRANST group (relevant for RUNTYP=TRANSITN)
(only for CITYP=GUGA or MPLEVL=2)
This group controls the evaluation of the radiative
transition moment, or spin orbit coupling (SOC). An SOC
calculation can be based on variational CI wavefunctions,
using GUGA CSFs, or based on 2nd order perturbation theory
using the MCQDPT multireference perturbation theory.
These are termed SOCI and SOMCQDPT below. The orbitals
are typically obtained by MCSCF computations, and since
the CI or MCQDPT wavefunctions are based on those MCSCF
states, the zeroth order states are referred to below as
the CASCI states. SOC jobs prepare a model Hamiltonian
in the CASCI basis, and diagonalize it to produce spin
mixed states, which are linear combinations of the CASCI
states. If scalar relativistic corrections were included
in the underlying spinfree wavefunctions, it is possible
either to include or to neglect similar corrections to the
spinorbit integrals, see keyword NESOC in $RELWFN.
An input file to perform SOCI will contain
SCFTYP=NONE CITYP=GUGA MPLEVL=0 RUNTYP=TRANSITN
while a SOMCQDPT calculation will have
SCFTYP=NONE CITYP=NONE MPLEVL=2 RUNTYP=TRANSITN
The SOC job will compute a Hamiltonian matrix as the sum
of spinfree terms and spinorbit terms, H = Hsf + Hso.
For SOCI, the matrix Hsf is diagonal in the CASCI state
basis, with the LScoupled CASCI energies as the diagonal
elements, and Hso contains only offdiagonal couplings
between these LS states,
Hsf = CASCI spinfree E
Hso = CAS SOC Hamiltonian (e.g. HSO1, HSO2P, HSO2)
For SOMCQDPT, the additional input PARMP defines these
matrices differently. For PARMP=0, the spinfree term
has diagonal and offdiagonal MCQDPT perturbations:
Hsf  CASCI spinfree E + 2nd order spinfree MCQDPT
Hso  CAS SOC Hamiltonian
For PARMP not equal to 0, the spin orbit operator is also
included into the perturbing Hamiltonian of the MCQDPT:
Hsf  CASCI spinfree E + 2nd order spinfree MCQDPT
Hso  CAS SOC Hamiltonian + 2nd order SOMCQDPT
Pure transition moment calculations (OPERAT=DM) are
presently limited to CI wavefunctions, so please use only
CITYP=GUGA MPLEVL=0. The transition moments computed by
SOMCQDPT runs (see TMOMNT flag) will form the transition
density for the CASCI zeroth order states rather than the
1st order perturbed wavefunctions.
Please see REFS.DOC for additional information on what
is actually a fairly complex input file to prepare.
OPERAT selects the type of transition being computed.
= DM calculates radiative transition moment
between states of same spin, using
the dipole moment operator. (default)
= HSO1 oneelectron SpinOrbit Coupling (SOC)
= HSO2P partial two electron and full 1e SOC,
namely coreactive 2e contributions are
computed, but activeactive 2e terms
are ignored. This generally captures
>90% of the full HSO2 computation, but
with spinorbit matrix element time
similar to the HSO1 calculation.
= HSO2 one and twoelectron SOC, this is the
full PauliBreit operator.
= HSO2FF one and twoelectron SOC, the form factor
method gives the same result as HSO2, but
is more efficient in the case of small
active spaces, small numbers of CASCI
states, and large atomic basis sets.
This final option applies only to SOCI.
PARMP = controls inclusion of the SOC terms in SOMCQDPT,
for OPERAT=HSO1 (default=1) or for HSO2P/HSO2
(default=3) only.
0  no SOC terms should be included in the MCQDPT
corrections at 2nd order, but they will be
included in the CAS states on which the MCQDPT
(i.e. up to 1st order)
1  include the 1e SOC perturbation in MCQDPT
1  defined under "3", read on...
3  full 1electron and partial 2electron in the
form of the mean field perturbation (this is
very similar to HSO2P, but in the MCQDPT2
perturbation). Only doubly occupied orbitals
(NMODOC) are used for the core 2e
contribution.
if the option is set to 1, then all core
orbitals (NMOFZC+NMODOC) are used. Neither
calculation includes extra diagrams including
filled orbitals, so both are "partial".
PARMP=3 (or 1) has almost no extra cost compared to
PARMP=1, but can only be used with OPERAT=HSO2 or HSO2P.
The options 1 and 3 are not rigorously justified, contrary
to HOS2P for a SOCI, as 2e integrals with 2 core indices
appear in the second order in two ways. There is a mean
field addition to 1e integrals, which is included when you
choose PARMP=3 or 1. But, there are separate terms from
additional diagrams that are not implemented, so that there
is some imbalance in including the partial 2e correction.
Nevetheless, it may be better to include such "partial"
partial 2e contributions than not to. Note that at first
order in the energy (the CASCI states) the Nelectron
terms are treated exactly as specified by OPERAT.
NFFBUF = sets buffer size for form factors in SOMCQDPT.
(applies only to OPERAT = HSO1, HSO2 or HSO2P).
This is a very powerful option that speeds up
SOMCQDPT calculations by precomputing the total
multiplicative factor in front of each diagram so
that the latter is computed only once (this is in
fact what happens in MCQDPT). It is not uncommon
for this option to speed up calculations by a
factor of 10. Since this option forces running
the SOCASCI part twice (due to the SOMCQDPT
Hamiltonian being nonHermitian), it is possible
that in rare cases NFFBUF=0 may perform similarly
or better. The upper bound for NFFBUF is NACT**2,
where NACT=NOCCNFZC. Due to the sparseness of
the coupling constants it is usually sufficient to
set NFFBUF to 3*NACT. To use the older way of
dynamically computing form factors and diagrams on
the fly, set NFFBUF to 0. Default: 3*(NOCCNFZC)
It is advisable to tighten up the convergence criteria in
the $MCQDx groups since SOC is a fairly small effect, and
the spinfree energies should be accurately computed, for
example THRCON=1e8 THRGEN=1e10.
PARMP has a rather different meaning for OPERAT=HSO2FF:
It refers to the difference between ket and bra's Ms,
1 do matrix elements for ms=1 only
0 do matrix elements for ms=0 only
1 do matrix elements for ms=1 only
2 do matrix elements for all ms (0, 1, and 1),
which is the default.
3 calculates form factors so they can be saved
* * * next defines the orbitals and wavefunctions * * *
NUMCI = For SOCI, this parameter tells how many CI
calculations to do, and therefore defines how
many $DRTx groups will be read in.
For SOMCQDPT, this parameter tells how many
MCQDPT calculations to do, and therefore defines
how many $MCQDx groups will be read in.
(default=1)
IROOTS, IVEX, NSTATE, and ENGYST below will all
have NUMCI values. NUMCI may not exceed 64.
You may wish to define one $DRTx or $MCQDx group for each
spatial symmetry representation occuring within each spin
multiplicity, as the use of symmetry during these separate
calculations may make the entire job run much faster.
NUMVEC = the meaning is different depending on the run:
a) spinorbit CI (SOCI),
Gives the number of different MO sets. This can
be either 1 or 2, but 2 can be chosen only for
FORS/CASSCF or FCI wavefunctions. (default=1)
If you set NUMVEC=2 and you use symmetry in any
of the $DRTx groups, you may have to use ISTSYM
in the $DRT groups since the order of orbitals
from the corresponding orbital transformation
is unpredictable.
b) spinorbit perturbation (SOMCQDPT),
The option to have different MOs for different
states is not implemented, so your job will have
only one $VEC1 group, and IVEX will not normally
be input. The absolute value of NUMVEC should be
be equal to the value of NUMCI above. If NUMVEC
positive, the orbitals in the $VEC1 will be used
exactly as given, whereas if NUMVEC is a negative
number, the orbitals will be canonicalized
according to IFORB in $MCQDx. Using NUMVEC=NUMCI
and IFORB=3 in all $MCQDx to canonicalize over all
states is recommended.
Note that $GUESS is not read by this RUNTYP! Orbitals must
be in $VEC1 and possibly $VEC2 input groups.
NFZC = For SOCI, this is equal to NFZC in each $DRTx
group. When NUMVEC=2, this is also the number of
identical core orbitals in the two vector sets.
For SOMCQDPT, this should be NMOFZC+NMODOC given
in each of the $MCQDx groups.
The default is the number of AOs given in $DATA,
this is not very reasonable.
NOCC = the number of occupied orbitals. For SOCI this
should be NFZC+NDOC+NALP+NAOS+NBOS+NVAL, but
add the external orbitals if the CASCI states
are CISD or FOCI or SOCI type instead of CAS.
For SOMCQDPT enter NUMFZC+NUMDOC+NUMACT.
The default is the number of AOs given in $DATA,
which is not usually correct.
Note: IROOTS, NSTATE, ENGYST, IVEX contain NUMCI values.
IROOTS = array containing the number of CASCI states to
be used from each CI or MCQDPT calculation.
The default is 1 for every calculation, which is
probably not a correct choice for OPERAT=DM runs,
but is quite reasonable for the HSO operators.
The total number of states included in the SOC
Hamiltonian is the summation of the NUMCI values
of IROOTS times the multiplicity of each CI or
MCQDPT. See also ETOL.
NSTATE = array containing the number of CASCI states to be
found by diagonalising the spinfree Hamiltonians.
Of these, the first IROOTS(i) states will be used
to find transition moments or SOC. Obviously,
enter NSTATE(i) >= IROOTS(i).
The default for NSTATE(i) is IROOTS(i), but might
be bigger if you are curious about the additional
energies, or to help the Davidson diagonalizer.
NSTATE is ignored by SOMCQDPT runs, and you must
ensure that your IROOTS input corresponds to the
KSTATE option in $MCQDx.
ETOL = energy tolerance for CI state elimination.
This applies only to SOCI and OPERAT=HSO1,2,2P.
After each CI finds NSTATE(i) CI roots for each
$DRTx, the number of states kept in the run is
normally IROOTS(i), but ETOL applies the further
constraint that the states kept be within ETOL of
the lowest energy found for any of the $DRTx.
The default is 100.0 Hartree, so that IROOTS is
the only limitation.
IVEX = Array of indices of $VECx groups to be used for
each CI calculation. The default for NUMVEC=2 is
IVEX(1)=1,2,1,1,1,1,1..., and of course for
NUMVEC=1, it is IVEX(1)=1,1,1,1,1...
This applies only to CITYP=GUGA jobs.
ENGYST = energy values to replace the spinfree energies.
This parameter applies to SOCI only.
A possible use for this is to use first or second
order CI energies (FOCI or SOCI in $DRT) on the
diagonal of the Hamiltonian (obtained in some
earlier runs) but to use only CAS wavefunctions
to evaluate off diagonal HSO matrix elements.
The CASCI is still conducted to get CI coefs,
needed to evaluate the off diagonal elements.
Enter MXRT*NUMCI values as a square array, by the
usual FORTRAN convention (that is, MXRT roots of
$DRT1, MXRT roots of $DRT2 etc), in hartrees, with
zeros added to fill each column to MXRT values.
MXRT is the maximum value in the IROOTS array.
(the default is the computed CASCI energies)
See B.Schimmelpfennig, L.Maron, U.Wahlgren,
C.Teichteil, H.Fagerli, O.Gropen Chem.Phys.Lett.
286, 261266(1998).
* * * the next pertain only to spinorbit runs * * *
RSTATE = sets the zero energy level
format: ndrt*1000+iroot for adiabatic state (root)
0000 sets zero energy to the lowest diabatic root
default: 1001 (1st root in $DRT1 or $MCQD1)
ZEFTYP specifies effective nuclear charges to use.
= TRUE uses true nuclear charge of each atom,
except protons are removed if an ECP basis
is being used (default).
= 321G selects values optimized for the 321G
basis, but these are probably appropriate
for any all electron basis set. Rare gases,
transition metals, and Z>54 will use the
true nuclear charges.
= SBKJC selects a set obtained for the SBKJC ECP
basis set, specifically. It may not be
sensible to use these for other ECP sets.
Rare gases, lanthanides, and Z>86 will use
the true nuclear charges.
ZEFF = an array of effective nuclear charges, overriding
the charges chosen in ZEFTYP.
Note that effective nuclear charges can be used for
any HSO type OPERAT, but traditionally these are used
mainly for HSO1 as an empirical correction to the
omission of the 2e term, or to compensate for missing
core orbitals in ECP runs.
ONECNT = uses a onecenter approximation for SOC integrals:
= 0 compute all SOC integrals without approximations
= 1 compute only onecenter 1e and 2e SOC integrals
= 2 compute all 1e, but only onecenter 2e integrals
Numerical tests indicate the error of the onecenter
approximation (ONECNT=1) is usually on the order of a
few wavenumbers for LiNe (a bit larger for F?) and its
errors appear to become negligible for anything heavier
than Ne. ONECNT=1 appears to give a better balanced
description than ONECNT=2. Very careful users can check
how well the approximation works for their particular
system by using ONECNT=0, then ONECNT=1, to compare
the results. One important advantage of ONECNT=1/2 is
that this removes the dependence of SOC 2e integrals
upon the molecular geometry. This means the program
needs to compute SOC 2e integrals only once for a given
set of atoms and then they can be read by using SOC
integral restart. RUNTYP=SURFACE automatically takes
advantage of this fact.
JZ controls the calculation of Jz eigenvalues
= 0 do not perform the calculation
= 1 do the calculation
By default, Jz is set to 1 for molecules that are
recognised as linear (this includes atoms!).
Jz cannot be computed for nonlinear molecules.
The matrix of Jz=Lz+Sz operator is constructed
between spinmixed states (eigenvalues of Hso).
Setting Jz to 1 can enforce otherwise avoided (by
symmetry) calculations of SOC matrix elements.
JZ applies only to HSO1,2,2P.
TMOMNT = flag to control computation of the transition
dipole moment between spinmixed wavefunctions
(that is, betweeen eigenvectors of the PauliBreit
Hamiltonian). Applies only to HSO1,2,2P.
(default is .FALSE.)
SKIPDM = flag to omit(.TRUE.) or include(.FALSE.) dipole
moment matrix elements during spinorbit coupling.
Usually it takes almost no addition effort to
calculate excluding some cases when the
calculation of forbidden by symmetry spinorbit
coupling matrix elements may have to be
performed since and are computed
simultaneously. Applies only to HSO1,2,2P.
Since the lack of a MCQDPT density matrix means
there are no MCQDPT dipole moments at present,
SOMCQDPT jobs will compute the dipole matrix
elements for the CASCI states only. However,
the dipole moments in the spinmixed states will
be computed with the MCQDPT mixing coefficients.
(default is .TRUE.)
IPRHSO = controls output style for matrix elements (HSO*)
=1 do not output individual matrix elements
otherwise these are accumulative:
= 0 termsymbol like kind of labelling:
labels contain full symmetry info (default)
= 1 all states are numbered consequently within each
spin multiplicity (ye olde style)
= 2 output only nonzero (>=1e4) matrix elements
PRTPRM = flag to provide detailed information about the
composition of the spinmixed states in terms of
adiabatic states. This flag also provides similar
information about Jz (if JZ set).
(default is .FALSE.)
LVAL = additional angular momentum symmetry values:
For the case of running an atom:
LVAL is an array of the L values (L**2 = L(L+1))
for each $MCQD/$DRT group (L=0 is S, 1 is P, etc.)
For the case of running a linear molecule:
LVAL is an array that gives the Lz values. Note
that realvalued wavefunctions (e.g. Pix, Piy)
have Lz and Lz components mixed, so you should
input Lz as 1 and 1 for both Pix and Piy.
This parameter should not be given for a nonlinear
polyatomic system.
Default: all set to 1 (that is, do not use these
additional symmetry labels. It is the user's
responsibility to ensure the values' correctness.
Note that for SOMCQDPT useful options in $MCQDPT
are NDIAOP and KSTATE. They enable efficient
separation of atomic/linear symmetry irreps).
It is acceptable to set only some values and leave
others as 1, if only some groups have definite
values. Note that normally Lz values are printed
at the end of the log file, so its easy to double
check the initial values for LVAL. For the case
of atoms LVAL drastically reduces the CPU time, as
it reduces a square matrix to tridiagonal form.
For the case of linear molecules the savings at
the spinorbit level are somewhat less, but they
are usually quite significant at the preceding
spinfree MCQDPT step.
MCP2E = Model Core Potential SOC 2e contributions.
Note that MCP 1e contributions are handled as in
case of allelectron runs because MCP orbitals
contain all proper nodes).
= 0 do not add the MCP 2e coreactive contribution,
but add any other 2e terms asked for by OPERAT.
= 1 add this contribution, but no other 2e SOC term.
This is recommended, and the default.
= 2 add this contribution and the 2e contributions
requested by OPERAT, for any e which are being
treated by quantum mechanics (not MCP cores).
Note that for MCP2E=0 and 2, HSO2, HSO1, HSO2P
values of OPERAT are supported for the explicit
2e contributions. The recommended approach is to
assume that MCP alone can capture all the 2e SOC,
for this use MCP2E=1 OPERAT=HSO2P. The entire 2e
contribution is achieved with MCP2E=2 OPERAT=HSO2.
If your MCP leaves out many core electrons as
particles, MCP2E=2 OPERAT=HSO2P can be tested to
see if it adds a sizable amount to SOC, compared
to MCP2E=1 OPERAT=HSO2P).
MCP2E=2 OPERAT=HSO1 is an illegal combination.
MCP2E=1 OPERAT=HSO1 is illogical since the MCP 2e
integrals are computed but not used anywhere.
The following table explains MCP2E and gives all
useful combinations:
MCP2E/OPERAT 2e SOC contributions SOC 2e ints
2 HSO2 MCPcoreCIact + CIcoreCIact MCP+basis
+ CIactCIact
2 HSO2P MCPcoreCIact + CIcoreCIact MCP+basis
1 HSO2P MCPcoreCIact MCP
using the following orbital space definitions:
MCPcore orbitals whose e are replaced by MCP
CIcore always doubly occupied
CIact MOs allowed to have variable occupation
* * * expert mode HSO control options * * *
MODPAR = parallel options, which are independent bit
options, 0=off, 1=on. Bit 1 refers only to
HSO2FF, bit 2 to HSO1,2,2P. Enter a decimal
value 0, 1, 2, 3 meaning binary 00, 01, 10, 11.
bit 1 = 0/1 (HSO2FF) uses static/dynamic load balancing in
parallel if available, otherwise use static
load balancing. Dynamic algorithm is usually
faster but may utilize memory less efficiently,
and I/O can slow it down. Also, dynamical
algorithm forces SAVDSK=.F. since its
unique distribution of FFs among nodes implies
no savings from precalculating form factors.
bit 2 = 0/1 (HSO1,2,2P) duplicate/distribute SOC integrals
in parallel. If set, 2e AO integrals and the
fourindex transformation are divided over
nodes (distributed), and SOC MO integrals are
then summed over nodes.
The default is 3, meaning both bits are set on (11)
PHYSRC = flag to force the size of the physical record to
be equal to the size of the sorting buffers.
This option can have a dramatic effect on the
efficency. Usually, setting PHYSRC=.t. is helpful
if the code complains that low memory enforces
SLOWFF=.TRUE., or you set it yourself. For large
active spaces and large memory (more precisely, if
reclen is larger than the physical record size)
PHYSRC=.TRUE. can slow the code down. Setting
PHYSRC to .true. forces SLOWFF to be .false.
See MODPAR. (default .FALSE.) (only with HSO2FF)
RECLEN = specifies the size of the record on file 40,
where form factors are stored. This parameter
significantly affects performance.
If not specified, RECLEN have to be guessed,
and the guess will usually be either an
overestimate or underestimate. If the former
you waste disk space, if the latter the program
aborts. Note that RECLEN will be different for
each pair of multiplicities and you must specify
the maximum for all pairs. The meaning of this
number is how many nonzero form factors are
present given four MO indices. You can decrease
RECLEN if you are getting a message "predicted
sorting buffer length is greater than needed..."
Default depends on active space. (only HSO2FF)
SAVDSK = flag to repeat the form factor calculation twice.
This avoids wasting disk space as the actually
required record size is found during the 1st run.
(default=.FALSE.) (only with HSO2FF)
SLOWFF = flag to choose a slower FF writeout method.
By default .FALSE., but this is turned on if:
1) not enough memory for the fast way is available
2) the maximum usable memory is available, as when
the buffer is as large as the maximum needed,
then the "slow FF" algorythm is faster.
Generally SLOWFF=.true. saves up to 50% or so of
disk space. See PHYSRC. (only with HSO2FF)
ACTION controls disk file DAFL30 reuse.
= NORMAL calculate the form factors in this run.
= SAVE calculate, and store the form factors on
disk for future runs with the same active
space characteristics.
= READ read the form factors from disk from an
earlier run which used SAVE.
(default=NORMAL) (only with HSO2FF)
Note that currently in order to use ACTION =
SAVE or READ you should specify MS= 1, 0, or 1
* * * some control tolerances * * *
NOSYM= 1 forces use of symmetrycontaminated orbitals
symmetry analysis, otherwise the same as NOSYM=0
= 0 fully use symmetry
= 1 do not use point group symmetry, but still use
other symmetries (Hermiticity, spin).
= 2 use no symmetry. Also, include all CSFs for
HSO1, 2, 2P.
= 3 force the code to assume the symmetry specified
in $DATA is the same as in all $DRT groups, but
is otherwise identical to NOSYM=1. This option
saves CPU time and money(memory). Since the $DRT
works by mapping nonAbelian groups into their
highest Abelian subgroup, do not use NOSYM=3 for
nonAbelian groups.
SYMTOL = relative error for the matrix elements. This
parameter has a great impact upon CPU time, and
the default has been chosen to obtain nearly
full accuracy while still getting good speedups.
(default=1.0E4)
* * * the remaining parameters are not so important * * *
PRTCMO = flag to control printout of the corresponding
orbitals. (default is .FALSE.)
HSOTOL = HSO matrix elements are considered zero if they
are smaller than HSOTOL. This parameter is used
only for printout and statistics.
(default=1.0E1 cm1)
TOLZ = MO coefficient zero tolerance (as for $GUESS).
(default=1.0E8)
TOLE = MO coefficient equating tolerance (as for
$GUESS). (default=1.0E5)
