With this award form the Inorganic, Bioinorganic and Organo- metallic Chemistry Program, Ronald L. Musselman of Franklin and Marshall College will investigate the electronic structures of metalloprotein model compounds and porphyrinic one-dimensional electrical conductors. Polarized specular (mirror-like) reflectance spectroscopy will be used in the study, which will probe metalloporphyrin complexes and thereby provide information that may be useful in understanding the mechanism of reactivity at the active sites in some non-heme binuclear proteins and enzymes. Polarized specular reflectance spectroscopy of single crystals is especially advantageous for study of visible and ultraviolet spectra of charge transfer transitions in metal complexes be- cause of their normally high intensities and high absorbancies. Two types of compouds to be studied are: (1) model compounds which mimic the binuclear metalloenzymes of copper and iron, such as hemocyanin and hemerythrin, and (2) partially oxidized metalloporphyrins which stack in such a manner so as to conduct electricity through the metal spine or through the pi-systems of the parallel macrocycles. The relative energy levels of metal- and ligand-based orbitals subject to partial oxidation and conductive band formation, as well as the electronic structure changes which occur upon aggregation of the discrete molecules into chains, will be determined. A special component of this research project will be heavy involvement of undergraduates.
