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OpenMolcas is a quantum chemistry software package to allow an accurate treatment of very general electronic structure problems for molecular systems in both ground and excited states.

OpenMolcas is available as a module on Apocrita.


To run the default installed version of OpenMolcas, simply load the openmolcas module:

$ module load openmolcas
pymolcas -h

usage: pymolcas [options] [input_file | script ...]

For full usage documentation, run pymolcas -h.

Example jobs

Serial job

Here is an example job running on 1 core and 1GB of memory:

#$ -cwd
#$ -j y
#$ -pe smp 1
#$ -l h_rt=1:0:0
#$ -l h_vmem=1G

module load openmolcas

pymolcas example.input

Parallel job

Here is an example job running on 96 cores across 2 ddy nodes with MPI:

#$ -cwd
#$ -j y
#$ -pe parallel 96
#$ -l infiniband=ddy-i
#$ -l h_rt=240:0:0

module load openmolcas

# Instruct the scheduler to spawn pymolcas processes on all execution
# hosts granted for the job.

pymolcas -np ${NSLOTS} example.input