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Computational Chemistry

The quality and efficiency of chemical processing, including shrinking the timelines for industrial process scale-up and optimizing processes to maximize yields and minimize unwanted wastes and byproducts, can be greatly enhanced through computer simulation.  However, reliable simulation of chemical processes is often inhibited by the lack of accurate chemical and physical property data for individual molecular species, mixtures, and reactions.  Industrial scientists and engineers are beginning to look to quantum chemistry as a source of timely and cost-effective estimates of needed property data.  This has generated an intense need for systematic testing, evaluation and benchmarking of quantum chemistry methods in order to establish the accuracy, reliability, applicability and relative merits of different computational tools/approaches for different problems.

The Computational Chemistry Group is developing databases and computational archives that will function as a resource for scientists and engineers who want to compare the economics and accuracy of various computational methods for estimating properties.  Current efforts are focussed on thermochemical and kinetic properties.  State-of-the-art computational methods are developed, tested, and evaluated.  Benchmark comparisons are made against accurate experimental data for classes of chemical compounds and reactions.  Databases of computational/experimental comparisons are developed in order to provide reliable estimates of the accuracy and precision of well-defined computational methods.

Long-range interests include: the development of computational methods for predicting reaction mechanisms and reaction rates in solution; the development of more accurate methods for determining the structures and thermodynamic properties of large molecules;  the development of new hybrid quantum chemistry methods with empirical corrections for predicting thermochemical properties;  the development of robust density functional methods that are applicable to transition states; and the development and testing of quantum chemistry methods for molecules containing heavy atoms.