SCHOLARS@TAMU

Bio-inspired Catalysts for Hydrogen Production: The ultimate, home-run, goal of our work is to synthesize and develop a robust, highly active hydrogen-producing catalyst comprised of earth-abundant transition metals within a ligand environment that is inspired by the biological Figure 3hydrogenase (H2ase) enzyme active sites. Progress in precise structural modeling of the illusive "rotated" structure displayed in the as-isolated, mixed-valent FeIIFe state in the past decade has permitted in depth analysis of electronic structure by Mo ssbauer, EPR (ENDOR), and computational chemistry. New electrocatalysts for hydrogen production: The connection between the Fe(NO)2 unit and the Fe(CX)3 (X = O or N) unit found in hydrogenase enzyme active sites offers opportunity for design of new catalysts, one of which is shown. In this regard we explore the ability of N2S2 metal complexes to bind as metallodithiolate ligands to various metal acceptors. The properties of such complexes vary The connection of these to light harvesting molecules for dye sensitized, sacrificial electron donor, hydrogen production is also of interest. When Iron Meets Nitric Oxide: Good Chemistry, Intriguing Biology. The affinity of iron for diatomic molecules, O2, CO, N2, and NO, is central to the most important of life processes, including those of human physiology. Figure 6In this research area we target synthetic chemistry involving dinitrosyl iron complexes (DNICs) that serve as biomimetics of products of FeS cluster degradation by excesses of NO, or as derived from the chelatable iron pool (CIP) in cells. The electronic ambivalence of the DNIC unit is expressed in the ease with which it interconverts between oxidized and reduced forms, {Fe(NO)2}9 and {Fe(NO)2}10, respectively (Enemark/Feltham notation), and serves as impetus to explore analogous reactions known to involve the CuII/CuI redox couple. The accessory ligands which stabilize one redox level over the other, including N-heterocyclic carb