In this project, which is supported by the Theoretical and Computational chemistry program, professor Schaefer at the University of Georgia will continue his investigations of the electronic structure of atoms and molecules and the reactions which they undergo. The research program is composed of two parts. The first is the development and testing of new methods, while the second is the application of these methods to relevant and interesting chemical problems. The methods to be developed are all aimed at a more accurate description of the potential energy surface(s) which describe a molecule and the energy changes once the molecule is distorted and reaction occurs. Of particular focus in this granting period will be an implementation of coupled cluster methods applicable to open shell species. Additionally Schaefer will investigate approximations to another electron-correlation method, namely second-order configuration interaction. During this grant period a number of chemical applications will also be pursed. A partial list of these projects includes: a detailed examination of the phenylcarbene/tropylidene potential energy surface; the equilibrium geometry of the ammonia dimer; an investigation of a direct iron-iron bond in the complex Fe2(CO)9. Further investigations will also probe whether hybrid density functional theory Hartree-Fock methods can resolve the apparent inconsistencies between molecular mechanics and experiment for the thermochemistry of C20H20.
