In this project in the Inorganic, Bioinorganic and Organometallic Chemistry Program the effects of applied electric fields on the absorption and emission spectra of a wide range of molecules, and on the rates of electron transfer reactions, will be examined. The results are expected to deepen our understanding of the factors which govern the rates and specificity of transfer of electrons within and between molecules. Experimental and theoretical methods which have been developed for studying the effects of electric fields in photosynthetic systems will be extended to non-biological systems. These approaches will be used to measure (1) the degree of charge separation in metal-to-ligand charge transfer and intervalence transitions in transition metal complexes, (2) the effects of applied electric fields on the electronic coupling between the donor and acceptor, (3) the degree of charge-transfer character in the excited states of donor-acceptor compounds which undergo electron transfer but whose absorption spectra are unaffected by the presence of the acceptor, (4) the effects of electric fields on the rates of electron transfer reactions or competing luminescence, and (5) the magnitude of the internal field correction for various polymeric matrices.