Additions/Revisions to GAMESS

June 27, 2005:
ZAPT2 parallel analytic gradients for open shell ROHF references may now be computed. A determinant based multireference perturbation theory program is provided, using direct CI techniques. Charge transfer and disperson terms are added to the EFP2 model, together with a more efficient exchange repulsion gradient. All Effective Fragment Potential computations may now be executed in parallel. The Coupled Cluster program permits the computation of CCSD(TQ) energies, and generation of the density matrix for CCSD or EOM-CCSD states. The Surface and Volume Polarization for Electrostatics continuum solvation model is included. The Fragment Molecular Orbital scheme has been generalized to a multi-level treatment of different fragments, and extended to include MCSCF and Coupled Cluster computations. Two families of systematic basis sets have been provided, namely the Polarization Consistent and Correlation Consistent sets.

November 22, 2004:
Two new codes for faster AO two electron integral evaluation are available, using rotated axis techniques to do s,p,d,L integrals, and precursor Hermite transfer equations for other high angular momentum cases. The accuracy of the TEI programs has been improved. The QFMM code has been extended to computation of nuclear gradients. The Quadratic Force Field approximation has been added to reduce time requirements for computation of anharmonic frequencies by vibrational SCF.

May 19, 2004:
Analytic hessians for full active space MCSCF wavefunctions are now coded, and enabled for scalable parallel calculation. EOM-CCSD excitation energies, and novel triples corrections to these, may be obtained for RHF references. The Polarizable Continuum Model (PCM) for solvent computations has been generalized for use by all SCF wavefunctions and their DFT counterparts, and now defaults to Conductor PCM with Area Scaling tesselation. The PCM interface with the EFP model has also been extended to all SCF types. The Fragment Molecular Orbital (FMO) method for the computation of very large molecules by linked computations of its subunits is included, for RHF or DFT energies and gradient, or MP2 energies.

This version of GAMESS is constructed on top of a new implementation of the Distributed Data Interface (DDI). The new DDI is optimized for SMP clusters, using SystemV memory calls to implement distributed memory operations inside nodes, and usually TCP/IP messaging between nodes. The installation procedure for GAMESS now has an additional new step for the compilation of DDI, and some systems may require reconfiguration to permit large SystemV memory allocations.

December 12, 2003:
Parallel computation of the CIS energy and its gradient for RHF references is possible. Relativistic quantum chemistry using a third order Douglas-Kroll transformation for the inclusion of scalar effects is included, along with the ability to compute Spin-Orbit Coupling with Model Core Potentials. Numerical differentiation of any of the available energy values to obtain the nuclear gradient or the nuclear hessian has been coded. An NMR program for RHF wavefunctions is also included.

July 3, 2003:
A distributed memory parallel UMP2 energy and gradient code based on DDI is now available. The Polarizable Continuum Model (PCM) solvation model now offers accurate nuclear gradients, allowing for PCM geometry searches. Finally, Model Core Potential (MCP) integrals are added, permitting energy calculations with correctly shaped valence orbitals.

January 14, 2003:
Occupationally Restricted Multiple Active Space (ORMAS) can be used as the CI step of MCSCF orbital optimizations, with fewer determinants than FORS (CAS-SCF).

June 20, 2002:
Closed shell reference coupled-cluster energies such as the standard CCSD and CCSD(T) models, and the completely renormalized CC-SD(T) model for bond breaking systems may be computed.

February 16, 2002:
The nuclear gradient for UMP2 wavefunctions may now be computed in serial fashion. Determinant-based direct second order CI computation is also available.