David Yarkony of Johns Hopkins University is supported by an award from the Theoretical and Computational Chemistry program for research on the development of techniques for systems in which the Born-Oppenheimer (BO) approximation breaks down, primarily during photochemical processes and other molecular events involving excited states. Yarkony is studying situations in which conical interactions involving three state intersections are important, particularly in free radical processes. Another goal of the research is the development of a set of propensity rules that can be used as guidelines for predicting excited-state decay. Yarkony is incorporating the algorithms he develops into an electronic structure computer code known as COLUMBUS which is freely available to other scientists, giving the work a broader impact, particularly in terms of cyberinfrastructure available for chemistry research.
