With the support of the Inorganic, Bioinorganic, and Organometallic Program, Dr. Ronald L. Musselman of the Chemistry Department, Franklin and Marshall University, will continue investigations of the electronic structure of oxygen-bridged iron and copper metalloproteins and of one dimensional conductors containing metalloporphyrins and square planar complexes. Single crystal specular reflectance spectroscopy will be utilized in characterizing intense charge transfer transitions in these transition metal complexes. The information obtained can help clarify the extent of movement of electrons through the metal backbone or through the pi-system of stacked macrocycles in conductive polymers. Similar information is also useful for understanding the mechanism of reactivity at the active site of non-heme binuclear proteins and enzymes, for which the bridged species are models. Electronic transitions in the visible, ultraviolet, and mid- infrared regions will be accessible on newly acquired instrumentation. %%% The information obtained from polarized reflectance spectroscopy assists in characterizing the energy and movement of electrons in solids. It is thus helpful in determining the optical properties of crystalline materials or other solids and films. The technique will be used here to explore the movement of electrons in systems related to biologically important proteins involved in oxygen and electron transport, and in conducting polymers. A number of undergraduate students and high school teachers will be involved in the conduct of the research.