John Tully of Yale University is supported by an award from the Theoretical and Computational Chemistry program for research to develop theoretical and computational methodologies for chemical dynamics in condensed phases and at surfaces. An ab initio approach based on constrained density functional theory is being developed for computing the electronic interactions that govern electron transfer rates. In addition, two new approaches are being explored for introducing quantum mechanical effects into simulations of atomic motions. The first is an outgrowth of Tully's configurational extension of the de Broglie-Bohm formulation of quantum mechanics; the second is a multiple-state generalization of the ring polymer molecular dynamics approach. The Tully group is applying these new techniques to the study of vibrational energy flow at surfaces, with emphasis on adsorbed hydrogen on silicon.
