Gaussian

Gaussian is a widely used computational chemistry code. It was installed on Aries and Bellatrix in November 2013.

Versions
Gaussian09 D.01, the latest version at the time was installed.

New versions can be installed if needed. Please contact Daniel Jana, the maintainer of Gaussian on Aries/Bellatrix, for that.

How to use it
First you have to load the module. You can do it with: $ module load gaussian/g09-d.01

This sets the right environment to use Gaussian09, including the PATH and all variables required. There is a wrapper, to set some stuff for Gaussian prior to usage. To run Gaussian you use something like: g09.aries input.inp > output.log     # In Aries g09.bellatrix input.inp > output.log # In Bellatrix

The parallelization of Gaussian is not very efficient. As a rule of thumb, you probably want to use less than all the cores on a node and put multiple jobs on the same node. This may involve a bit of planning, but leads to a more efficient use of the limited resources available. Which means, in the long run, you get more calculations finished in less time. Also, we are discouraging use of more than one node per calculation. The scalability does not justify it. To get your jobs to run you could use resource lines like this:
 * 1) PBS -l place=shared
 * 2) PBS -l select=1:ncpus=8:mem=7000mb

on the top of your script. This specific case tells the node can be shared with other jobs. It also asks for 8 CPU processes with 7000 MB of RAM. Any of these numbers can be changed, depending on your needs.

Do I have access to it?
It is available to all members of the gaussian-soft group. You can check if you are a member of the group by using the command "id". You will see something like: $ id uid=33333(myusername) gid=10111(myunit) groups=65115(dit-clusters-users),65359(bellatrix-users),65830(gaussian-soft)

You may have a different set of groups but you need gaussian-soft to be there. Trying to load the module without belonging to the group will result in a warning message.

How to get the right to use it?
If you are not part of the gaussian-soft group contact Daniel Jana. He'll inform you on how to be proceed.