1 Feb 2011

NWCHem on Ubuntu Linux

This article has been written as instruction for my friend how to run NWChem.

What is NWChem?

From Wikipedia:

NWChem is an ab initio computational chemistry software package which also includes quantum chemical and molecular dynamics functionality. It was designed to run on high-performance parallel supercomputers as well as conventional workstation clusters. It aims to be scalable both in its ability to treat large problems efficiently, and in its usage of available parallel computing resources.

Why should I use NWChem?

Because it can handle:
  • Biomolecules, nanostructures, and solid-state
  • From quantum to classical, and all combinations
  • Gaussian basis functions or plane-waves
  • Scaling from one to thousands of processors
  • Properties and relativity

Before NWChem compilation

apt-get install build-essential gfortran

NWChem compilation

tar -xvzf ../Nwchem-6.0.tar.gz 
cd nwchem-6.0/
export NWCHEM_TOP=`pwd`
cd src/
export FC=gfortran
export NWCHEM_TARGET=LINUX64
make nwchem_config NWCHEM_MODULES=all
make
cd ../bin/LINUX64/
./nwchem

After running nwchem you probably get segfault (are you sure you have X windows session available?). Installation can be done using make install command executed in nwchem-6.0/src/

Additional notes

  • Use Intel compiler when you have Pentium4/Xeon (+30-40% performance gain) or PentiumIII/AMD (+10-20% performance gain).
  • pgf77 (Portland Group Compiler) is not fully supported
  • GNU fortran compiler (g77) on x64 is not encouraged because of the NWChem default use of 64-bit integers on 64-bit architectures