CPMD stands for Car-Parrinello Molecular Dynamics. It is an ab initio Electronic Structure and Molecular Dynamics Program.  This package is installed on the MCSR SGI Origin 2800 supercomputer. The CPMD program is started with the following command in a PBS script (named cpmd.pbs) on the Origin 2800. (An example script (cpmd.pbs) and input file (example3a.in) may be copied from /usr/local/appl/cpmd/examples on sweetgum).

 

#PBS -S /bin/csh

#PBS -l cput=3:00:00

#PBS -l ncpus=X

#PBS -l mem=XXXXMB

cd $userdir

mpirun –np 4 cpmd.x file.in [PP_path] > file.out

To submit the job to PBS, simply type this command:

%qsub cmpd.pbs

Running cpmd.x requires the following files:

• an input file file.in
• pseudopotential files for all atomic species specified in file.in

The path to the pseudopotential library can be given in different ways:

• The second command line argument [PP_path] is set.
• If the second command line argument [PP_path] is not given, the program checks the environment variables
  CPMD_PP_LIBRARY_PATH and PP_LIBRARY_PATH.
• If neither the environment variables nor the second command line argument are set, the program assumes that the pseudopotential files are in the current directory

The following is an example of input file for a CPMD job:

 

&CPMD

  MOLECULAR DYNAMICS

  TEMPERATURE

     300

  TEMPCONTROL IONS

     200 100

  PRINT

      1

  MAXSTEP

      400

  STORE

      50

  TIMESTEP

      6.0

  EMASS

    800.0

  COMPRESS READ WRITE

  SPLINE POINTS

     900

  MOVIE SAMPLE

     5

&END

 

 

&SYSTEM

  ANGSTROM

  SYMMETRY

    2

  CELL

    10.0  0  0  0  0  0

  CUTOFF

    70.0

  CHARGE

     0.0

  STATES

     5

&END

 

&ATOMS

*O_SG_BLYP

   LMAX=P

   1

   0.00000         0.00000         0.00000

*H_SG_BLYP

   LMAX=S

   2

   1.05000         0.00000         0.00000

  -0.35000         0.98995         0.00000

&END

 

&DFT

  NEWCODE

    FUNCTIONAL BLYP

  GC-CUTOFF

    0.1E-05

&END