Supercomputer chemistry

Quantum mechanics gives a mathematical description of the behavior of electrons that has never been found to be wrong. However, the quantum mechanical equations have never been solved exactly for any chemical system other than the hydrogen atom. Thus, the entire held of computational chemistry is built around approximate solutions. Some of these solutions are very crude and others are expected to be more accurate than any experiment that has yet been conducted. There are several implications of this situation. First, computational chemists require a knowledge of each approximation being used and how accurate the results are expected to be. Second, obtaining very accurate results requires extremely powerful computers. Third, if the equations can be solved analytically, much of the work now done on supercomputers could be performed faster and more accurately on a PC. 

Another important consideration is the amount of labor necessary on the part of the user. One major difference between different software packages is the developer s choices between ease of use and efficiency of operation. For example, the Spartan program is extremely easy to use, but the price for this is that the algorithms are not always the most efficient available. Many chemistry users begin with software that is very simple, but when more sophisticated problems need to be solved, it is often easier to learn to use more complicated software than to purchase a supercomputer to solve a problem that could be done by a workstation with different software. 

This book grew out of a collection of technical-support web pages. Those pages were also posted to the computational chemistry list server maintained by the Ohio Supercomputer Center. Many useful comments came from the subscribers of that list. In addition, thanks go to Dr. James F. Harrison at Michigan State University for providing advice born of experience. 

To address these challenges, chemical engineers will need state-of-the-art analytical instruments, particularly those that can provide information about microstmctures for sizes down to atomic dimensions, surface properties in the presence of bulk fluids, and dynamic processes with time constants of less than a nanosecond. It will also be essential that chemical engineers become familiar with modem theoretical concepts of surface physics and chemistry, colloid physical chemistry, and rheology, particrrlarly as it apphes to free surface flow and flow near solid bormdaries. The application of theoretical concepts to rmderstanding the factors controlling surface properties and the evaluation of complex process models will require access to supercomputers. 

Xhe 1987 WINTER SYMPOSIUM of the Division of Industrial and Engineering Chemistry, hosted by the Minnesota Supercomputer Institute, was supported by grants from the American Chemical Society, the Minnesota Supercomputer Institute, Cray Research, Inc., and ETA Systems, Inc. The symposium consisted of four half-day sessions with four lectures per session and a two-part poster session with 15 poster papers. This book includes chapters by the lecturers plus five papers contributed by the session chairs. All contributions were refereed anonymously according to usual procedures of the ACS Symposium Series. 

Donald G. Truhlar Minnesota Supercomputer Institute and Department of Chemistry University of Minnesota Minneapolis, MN 55455... 

In Supercomputer Research in Chemistry and Chemical Engineering Jensen, K., el al. ACS Symposium Series American Chemical Society Washington, DC, 1987. 

Minnesota Supercomputer Institute and Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455 Minnesota Supercomputer Institute and Department of Chemistry, University of Minnesota, Minneapolis, MN 55455... 

This chapter gives a selected overview of the current status of supercomputing research In chemistry and chemical engineering and places the research areas discussed In the rest of the book In the context of current work. 

Lykos, P. Shavltt, I. Supercomputers in Chemistry American Chemical Society Washington, 1981. 

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