THE DESIGN AND PREPARATION OF TRANSITION-METAL TRIAD SYSTEMS FOR EXCITED-STATE CHARGE SEPARATION

A series of multimetal complexes have been prepared with the intent of mimicking the charge separation process that occurs in photosynthesis . The systems have three component parts: antenna or absorbing fragmen t, electron donor, and electron acceptor. Synthetic modification of th ese components and the spacers which covalently couple these component s will be discussed in terms of the thermodynamics and kinetics leadin g to the formation and lifetime of the charge-separated state. Systems with polyazine ruthenium(II) antenna, cyanoferrate(II) electron donor s and a viologen electron acceptors will be described which have a lif etime of 37 - 86 ns.