This grant in the Inorganic Chemistry Program will support continued work on the synthesis of heterobimetallic compounds which consist of a main group heteroatom, e.g., sulfur, and one or more metals selected from the sets, (molybdenum or tungsten) and (iron, cobalt, or nickel) tightly bonded together in a cluster. The chemical reactions of the clusters with molecules of interst in catalysis, e.g., CO, hydrogen, alkynes, thiophene, etc., will be determined, as will the reactions of the clusters with the surface metal oxide supports. It has been found that these new clusters show interesting selectivities in the catalysis of CO hydrogenation and hydrodesulfurization when supported on the surface of metal oxides. It is proposed to determine the nature of the ensembles present on the oxide surfaces and elucidate their mode of catalytic action. The compounds which will be synthesized and studied show promose as selective and efficient catalysts for a variety of important chemical processes, such as the reaction of carbon monoxide with hydrogen. Some of these compounds decompose upon heating to form highly reactive small clusters of metal atoms which may also be useful as catalysts.
