NSF Award
8711549
Previous participants in this research project at a primarily undergraduate institution have included a number of students currently enrolled in PhD programs in major chemistry departments. The project is expected to provide much-needed information about the mechanisms of structural transformations of metal cluster compounds. Such compounds are an important class of catalysts and are also important as precursors for the preparation of new solid materials. The photochemical synthesis of mixed transition metal clusters from mercury bridged mixed transition metal clusters (containing M = Ru, Os and M'= group VI thru group VIII, first, second or third row transition metal moiety) will be investigated. Crossover experiments using suitably labelled complexes will be conducted in order to evaluate the molecularity of the photo-induced reductive elimination of mercury which leads to formation of M2M'clusters and also to investigate the thermal exchange reactions between the starting clusters. The electron transfer chemistry of these mercury bridged metal clusters will be examined with a view towards promoting reductive elimination of mercury electro- chemically. The mechanisms of hydrogen transfer between coordinated ligands and the metal core (and the reverse reaction), in polynuclear metal clusters will be studied utilizing the observed kinetic deuterium isotope effects on these processes. The mechanisms of hydrogen transfer between metal atoms in polynuclear transition metal clusters and the relationship of this process to other ligand migrations will be studied utilizing the kinetic deuterium isotope effects previously documented for hydrogen migrations in several hydrido-metal clusters.
