SPECTROSCOPIC AND PHOTOPHYSICAL STUDIES OF APPARENT CLUSTER-TO-ORGANIC-ACCEPTOR CHARGE-TRANSFER IN A MOLECULAR CADMIUM-SULFIDE ASSEMBLY

A nitrobenzene (NB) decorated cadmium sulfide cluster, [Cd-4(S-NB)(10) ][N(CH3)(4)](2), has been prepared and examined spectroscopically. The assembly exhibits an intense cluster-to-attached-acceptor charge-tran sfer band at 376 nm. Observation of back electron transfer (nitrobenze ne to cluster) via time resolved luminescence yields a rate constant o f greater than or equal to 5 x 10(9) s(-1). Raman studies show that se ven vibrational modes are coupled to the electron transfer reaction an d that those exhibiting the greatest initial-state/final-state displac ements are the Cd-S and N-O stretches. Despite the activity of nu(Cd-S ), however, the electron donor is more appropriately characterized as an individual sulfur atom, rather than a delocalized assembly.