Gaussian

Gaussian is an electronic structure modeling program that Atlas has licensed for its HPC clusters that support AVX2 set of instructions (currently Atlas). To see available versions of Guassian on the cluster, run:

$ module spider Gaussian
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Gaussian:
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Versions:
     Gaussian/09
     Gaussian/16

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For detailed information about a specific "Gaussian" module (including how to load the modules) use the module's full name.
For example:

     $  module spider Gaussian/16
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However, before trying to run Gaussian, please, make sure your user belongs to either g09 or g16 Unix group. If this is not the case, please, email any of the staff members of the Computing Center.

Usage

In most cases, the scratch storage location (set by the environment variable GAUSS_SCRDIR) should be on the local parallel file system of the cluster (/scratch) or the local lscratch filesystems (/lscratch). In case you fail to define this variable within the batch script, the value of this variable will be the same as $PBS_O_WORKDIR, that is, the directory from which the job was submitted.

Before running Gaussian, you must set up a number of environment variables. This is accomplished most easily by loading the Gaussian module file using:

$ module load Gaussian/16

Example of a batch script that can be used as a template to submit Gaussian 16 jobs:

#!/bin/bash
#PBS -q parallel
#PBS -l nodes=1:ppn=24
#PBS -l mem=50gb
#PBS -l cput=1000:00:00
#PBS -N Gaussian_job

# Define working directory, copy relevant data, and change directory
export SCRATCH_DIR=/scratch/$USER/jobs/$PBS_JOBID
mkdir -p $SCRATCH_DIR
cd $PBS_O_WORKDIR
cp -r * $SCRATCH_DIR
cd $SCRATCH_DIR
export GAUSS_SCRDIR=$SCRATCH_DIR

# Load environment for Gaussian
module load Gaussian/16

# Define number of cores and number of nodes
export NPROCS=`wc -l < $PBS_NODEFILE`
export NODES=`uniq $PBS_NODEFILE | awk '{printf("%s,", $0)}' | sed 's/.$//'`

# Insert nodes and cores in the header of the input file
echo "%NProcShared=$NPROCS" > INPUT
echo "%LindaWorkers=$NODES" >> INPUT
cat my_input_file.com >> INPUT

g16 < INPUT >& output.log

Notice that you do not need to specify the number of cores and nodes in your input file if you use the example above as a template, because the script will take care of it.

GaussView 6

GaussView is a visualization program that can be used to open Gaussian output files and checkpoint files (.chk) to display structures, molecular orbitals, normal modes, etc. You can also set up jobs and submit them directly.

GaussView 6 on Atlas

The GaussView version for Gaussian 16 is release 6. To load and run GaussView on Atlas, you first have to load the corresponding Gaussian module, and then call GaussView:

$ module load GAUSSIAN/16
$ gv

Remember that you need to enable X11 forwarding to be able to open a graphical window.