Gaussian is a computational chemistry suite of programs used for electronic structure modelling. Gaussian is named after the type of orbitals used to speed up Hartree-Fock calculations - Gaussian orbitals rather than Slater-type orbitals. The software uses ab initio calculations to predict the energy, molecular structure, vibrational frequencies, and molecular properties of molecules and reactions in a variety of chemical environments. Key features of the software include investigations of molecules and reactions, predicting and interpreting spectra, and exploring diverse chemical arena.
The current version of the software is Gaussian09.The software runs in serial and in parallel. See here for the documentation for Gaussian09.
Parallelism with Gaussian
Please note that the version available on TCHPC Systems does not have the Linda parallelisation component. Parallel performance is however available within a single node, using the
%NProcShared parameter in the Gaussian input file.
For example, Lonsdale has 8-core nodes, so add the following line to the top of your input file:
A license is required to run Gaussian. The current TCD Gaussian licenses have been kindly provided by the Department of Chemistry.
Please note however that due to license restrictions, only groups which have purchased licenses are permitted to run Gaussian. If you have licenses for Gaussian and would like to discuss installing them on the TCHPC clusters, or, if you'd like to gain access to Gaussian, please contact us to discuss it.
How do I access the IITAC/Lonsdale clusters?
- For IITAC, ssh to login01.tchpc.tcd.ie.
- For Lonsdale, ssh to lonsdale.tchpc.tcd.ie.
See here for more details on Logging In
How do I run the Gaussian software?
Gaussian is part of the module system (see Environment Modules).
So you would run:
module load apps gaussian
to add it to your environment, or alternatively add that line to your ~/.bashrc to make sure that it is always loaded.
As noted above, the 'module load apps gaussian' line will fail if you are not in the correct group and do not have access to licenses.
Running via the batch system
You can run Gaussian through the queuing system either interactively or in batch.
Firstly, get an allocation:
salloc -N 1 -p compute -t 01:00:00 -U project_name
You will have to adjust the parameters above to suit, in particular you will need to use the correct project_name for your group.
Then, launch Gaussian as follows:
srun g03 < input > output
For general instructions on how run an interactive job, see here.
For this, you will need a submission script such as:
#SBATCH -N 1
#SBATCH -t 01:00:00
#SBATCH -p compute
#SBATCH -U project_name
#SBATCH -J job_name
g03 < input > output
For general instructions on how submit a batch job, see here.