The Inorganic, Bioinorganic, and Organometallic Chemistry Program supports research in the fundamental photochemistry of transition metal organometallic and coordination compounds. The studies described in this proposal on relaxation dynamics of spin equilibrium complexes have practical relevance to the field of optical information storage, and the work on detecting and characterizing reactive organometallic intermediates has practical importance to catalysis and surface chemistry. It is proposed to investigate the fundamental chemical and physical mechanisms governing the reactions and other deactivation processes of excited states and reactive intermediates formed by the photoexcitation of transition metal organometallic and coordination compounds. A major emphasis is placed on the use of flash lamp and laser pulse photolysis with time resolved luminescence and transient absorption spectral techniques to prepare and to characterize these short-lived species and to study quantitatively their reaction dynamics as functions of the nature and condition of the reaction medium. Specific systems proposed as part of these continuing studies include 1) strongly luminescent complexes of copper(I), platinum(II) and rhodium(III); 2) iron(II) compounds displaying quintet/singlet spin equilibria and 3) catalytically active phosphine complexes of rhodium and iridium plus certain metal carbonyl clusters.
