Molecular interactions in metalloproteins will be studied using resonance Raman (RR) spectroscopy as a probe of structure. Emphasis will be placed on iron-sulfur cluster, for which reliable assignments and force fields are under development. A computer modelling approach t the interpretation of Fe-S protein RR spectra is planned. The non-redox Fe-S proteins aconitase and dihydroxy acid dehydratases will be examined with a view to understanding the nature of enzyme-substrate interactions. The coupling of Fe-S cluster and siroheme chemistry in sulfite reductase will be probed. Molybdenum redox proteins will be studied to elucidate the structure of the active molybdopterin cofactor. Copper proteins will be examined in their reduced state using ultraviolet RR spectroscopy to utilize enhancement of bound ligand modes via metal->ligand charge transfer transitions.