The Theoretical and Computational Chemistry Program is supporting Professor Davidson at Indiana University. Over the next three years he will continue his development and application of new methodologies in the field of quantum chemistry for the purpose of understanding the very fundamental inner workings of molecules. The major focus of this theoretical research is in the area of multi-reference perturbation theory. Another aspect of this work involves the development of an alternative formulation of open shell density functional theory. This research will also continue investigations of a number of chemical systems, particularly of unstable forms of molecules. Computational chemistry has become very proficient at describing the properties of stable species. Chemical reactions of hot molecules are much more difficult to describe because the electrons in a reacting molecule are often distributed in ways that differ greatly from their behavior in stable molecules. Application of many standard computational methods often provides inaccurate and misleading predictions for reacting molecules. This research aims to improve methods designed to follow chemical reactions and to predict their outcomes. This requires developing methods that apply to fragments of molecules and to molecules with partially broken bonds. These methods will be tested by collaborating with experimental research groups that have compiled some information for a few well chosen reactions.
