NWChem

Description

NWChem is a computational chemistry package designed to run on high-performance parallel supercomputers. Code capabilities include the calculation of molecular electronic energies and analytic gradients using Hartree-Fock self-consistent field (SCF) theory, Gaussian DFT, and second-order perturbation theory. For all methods, geometry optimization is available to determine energy minima and transition states. Classical molecular dynamics capabilities provide for the simulation of macromolecules and solutions, including the computation of free energies using a variety of force fields.

NWChem is scalable, both in its ability to treat large problems efficiently and in its utilization of available parallel computing resources. The code uses the parallel programming tools TCGMSG and the Global Array (GA) library. NWChem has been optimized to perform calculations on large molecules using large parallel computers, and it is unique in this regard.

For more information, please see the NWChem home page.

Use

Phoenix
On Phoenix, NWChem is available as a module.
Prior to running NWChem, a .nwchemrc file should exist in your $HOME directory. After loading the NWChem module, the default can be copied with the following command:

cp $DEFAULT_NWCHEMRC $HOME/.nwchemrc

The following Portable Batch System (PBS) script will run the NWChem example case dna.nw on four single-streaming processors (SSPs):

#!/bin/csh
#PBS -N nwchem-test
#PBS -A projectid
#PBS -j oe
#PBS -q batch
#PBS -l walltime=1:00:00,mppe=1   

aprun -n4 nwchem dna.nw

If the script is named nwchem.pbs, it can be submitted with the following:

qsub nwchem.pbs