Table of Contents

	Capabilities of NWChem
	Running NWChem at the AHPCC
	Where to find more information about NWChem
	Legal Details

Capabilities of NWChem

Quick Summary of supported methods.

• SCF energies, gradients, and frequencies (RHF, ROHF, UHF).
• MP2 energies and gradients (RHF, ROHF, UHF).
• LSDA, BLYP, Becke88, etc. energies, gradients, and frequencies (RHF, ROHF, UHF).

Running NWChem at the AHPCC

To run NWChem follow these steps:

	Follow the instructions in the getting started section.
	Prepare an input file and append .nw to the name, i.e. h2o.nw.
	Run the calculation with the command "nwchem h2o" substituting the prefix of your input file for h2o.
	You may be asked platform specific information, such as the number of nodes you wish to use. Answer these prompts as you wish.
	NWChem will create an output file with the same prefix as your input file, i.e. h2o.out.

A sample input file is shown below. This will run a RHF/3-21G single point calculation on N₂. If the input file had the name n2.nw you would run the calculation with the command "nwchem n2". The output file will have the name n2.out.

start n2
title; nitrogen
memory total 16 mb
geometry units angstrom
  n 0.0 0.0 0.0
  n 0.0 0.0 1.1
end
basis
  n library 3-21G
end
task scf

Take a look at the output file produced by the above input file.

Where to find more information about NWChem

The NWChem manual is available in postscript format at ~chem/nwchem/manuals or in html format here. This document describes the input format and all input options in great detail.

A large number of sample input and output files can be found in the ~chem/nwchem/examples directory.

Two official methods of communication with the authors of NWChem are available. General questions should be sent to nwchem-users@emsl.pnl.gov while specific bugs should be send to nwchem-support@emsl.pnl.gov.

Also, check out the NWChem home page.

Legal Details

NWChem is developed and distributed by Pacific Northwest Laboratory and made available via an EMSL software agreement.

Literature Citation:

1. D. E. Bernholdt, E. Apra, H. A. Fruchtl, M.F. Guest, R. J. Harrison, R. A. Kendall, R. A. Kutteh, X. Long, J. B. Nicholas, J. A. Nichols, H. L. Taylor, A. T. Wong, G. I. Fann, R. J. Littlefield and J. Nieplocha, "Parallel Computational Chemistry Made Easier: The Development of NWChem," Int. J. Quantum Chem. Symposium 29, 475-483 (1995).

Copyright:

COPYRIGHT (C) 1994, 1995, 1996, Pacific Northwest National Laboratory, Battelle Memorial Institute.