Electrochemical Variational Study of Donor/ Acceptor Orbital Mixing and Electronic Coupling in CyanideBridged Mixed-Valence Complexes
نویسنده
چکیده
Cyanide-bridged mixed-valence complexes featuring metal(111) pentaammine acceptor sites and metal(I1) hexacyano donor sites have been investigated extensively by Vogler et aI.,l Haim and Burewicz,2 Shepherd et al.,3 and otherse4 These complexes are interesting examples of strongly covalently linked redox systems which, nevertheless, exist in valence-localized form. As mixed-valence species, they display fairly intense intervalence (or metal-to-metal) charge-transfer transitions ( E = 3000 M-I cm-I), which tend to be shifted toward the visible region from the near-infrared on account of substantial redox Our own interests center on bridge-mediated charge-transfer kinetics. We have recently succeeded5 in obtaining (by femtosecond transient absorbance spectroscopy) a direct measure of the thermal kinetics ET) of the highly exothermic back-electrontransfer reaction which follows intervalence excitation in one of these complexes, (H3N) jRu-NC-Fe( CN),-:
منابع مشابه
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