9723840 Fleming This award supports a two-year collaborative research project between Dr. Graham Fleming of the University of Chicago and Dr. Minhaeng Cho of Korea University on "Femtosecond Nonlinear Spectroscopy of Photosynthetic Light Harvesting." The goal of the project is to extend current theories of nonlinear spectroscopy, such as the photon echo, to include the influence of molecular dynamics. The three pulse echo peak shift method will be studied theoretically and applied experimentally to bacterial and plant systems to investigate: 1) degree of electronic delocalization, 2) energy transfer mechanisms, and 3) how the couplings of chromaphores to the protein environment influence electronic coupling. The collaboration between Dr. Fleming and Dr. Cho will enable a combined experimental and theoretical study of nonlinear spectroscopy applied to photosynthetic light harvesting. Dr. Fleming's laboratory has the capability of generating experimental data on the bacterial and plant antenna photosynthetic systems, while Dr. Cho has the theoretical expertise to develop the theoretical formalisms and computer codes to model these data. The study is timely because of the rapid advances in the structural biology of photosynthetic systems and in the techniques of nonlinear spectroscopy. It is expected that this study will result in a better understanding of the photosynthetic process and will form the basis for applying nonlinear spectroscopy as a probe of a wide range of chemical and biological dynamics. ***
