The dynamics of photochemical and electrochemical processes for molecules adsorbed on roughened silver and gold electrodes will be examined using surface-enhanced Raman Scattering (SERS) to monitor the kinetics and chemistry of the reactions. SERS will be used in a time-resolved mode using pump-probe techniques to follow concentration-time profiles and structural changes of reactants, intermediates and products in the nanosecond time domain. The studies will be directed towards (1) photochemical and electrochemical bond cleavage reactions of carbon-halide bonds in various halide-substituted ring compounds of piperidines, pyridines and quinolines and (2) the mechanisms of photoglavanic (solar energy conversion) processes for flavin molecules and other dye sensitizers adsorbed on roughened electrodes. The study promises to detect the excited state redox species near the electrode surface. %%% The research, in the general area of Analytical and Surface Chemistry, focuses on the use of surface-enhanced Raman Scattering to examine molecules on gold and silver electrode surfaces. The work promises to lead to a better understanding of the kinetics and chemistry of reactions that occur on these electrode surfaces, including processes that are important in solar energy conversion.