Model for binding of water to a model of single-layer graphite.

Predicted structure for cesium cation binding to a tetramethoxycalix[4]arene.

Electrostatic potential of the lipopolysaccharide membrane of a microorganism.

To model and simulate major environmental problems, scientists need more than the most powerful computers. They also need software algorithms that express the fundamental physics involved in entirely new ways, appropriate to parallel processing. Software of this type was developed recently by computational scientists, applied mathematicians, and theoretical chemists from the Pacific Northwest National Laboratory. Northwest Computational Chemistry Software (NWChem) is an advanced molecular modeling package featuring major design improvements over traditional codes, including new algorithms for computational chemistry and the high-level data and control structures needed to make parallel programs easier to write, maintain, extend, and use on a broad range of parallel computers. NWChem provides many methods for computing the properties of molecular systems by using quantum mechanics based on either molecular orbital theory or density functional theory. The software also can perform classical molecular dynamics and free-energy simulations of macromolecular and solution systems. For the first time, these approaches can be readily combined to perform mixed quantum mechanics and molecular dynamics simulations.

Scientific Impact: Developed in the mid-1990's at PNNL's Environmental Molecular Sciences Laboratory (EMSL), NWChem has been distributed to more than 300 sites worldwide, including most federal supercomputing centers and many universities. Scientists are using it to run modeling and simulation studies of DOE's environmental problems and other subjects, from combustion to petrochemical zeolite catalysts.

Social Impact: Studies using this software are addressing health and environmental issues and thus may eventually affect everyday life. NWChem has been used to study, for example, protein models for drug design, DNA chips, catalysts for the petroleum industry, geochemical surfaces for bioremediation, and atmospheric pollutants including aerosols.

Reference: Kendall, R.A., Aprà, E., Bernholdt, D.E., Bylaska, E.J., Dupuis, M., Fann, G.I., Harrison, R.J., Ju, J., Nichols, J.A., Nieplocha, J., Straatsma, T.P., Windus, T.L., Wong, A.T., "High Performance Computational Chemistry; an Overview of NWChem a Distributed Parallel Application," Computer Phys. Comm. 128, 260 (2000).

Guest, M.F., Aprà, E., Bernholdt, D.E., Früchtl, H.A., Harrison, R.J., Kendall, R.A., Kutteh, R.A., Long, X., Nicholas, J.B., Nichols, J.A., Taylor, H.L., Wong, A.T., Fann, G.I., Littlefield, R.J., Nieplocha, J., "High-Performance Computing in Chemistry; NWChem," Future Generations Computer Systems 12(4), 273, (1996).

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

URL: http://www.emsl.pnl.gov:2080/capabs/mscf/decades.htm (Click on Molecular Science Software Suite.)

Technical Contact: Mr. Paul Bayer, Environmental Sciences Division, Office of Biological and Environmental Research, 301-903-5324

Press Contact: Jeff Sherwood, DOE Office of Public Affairs, 202-586-5806

SC-Funding Office: Office of Biological and Environmental Research