On the mechanism of the photoinduced reduction of an adduct of ferricytochrome C with a poly(4-vinylpyridine) polymer containing -ReI (CO)3(3,4,7,8-tetramethyl-1,10-phenanthroline) pendants

Changes in the UV-vis absorption spectrum revealed the formation of adducts between the Re-I polymer and ferricytochrome C, Fe-III-Cyt c. Different morphologies for the Re-I polymer and the adducts formed between the Re-I polymer and Fe-III-Cyt c were observed by TEM. The reduction of the Re-I chromophores in the polymer, achieved by the reductive quenching of the MLCT excited state of the Re-I polymer by triethylamine (TEA) and/or by the reaction between e(solv)(-) and {[(vpy)(2)vpyRe(I)(CO)(3)(tmphen)(+)]}(n similar to 200) in pulse radiolysis experiments, produces -Re-I(CO)(3)(tmphen)(center dot) and -Re-I(CO)(3)(tmphenH)(center dot+) as the main species. The reductive quenching of the MLCT of the Re-I polymer by TEA was followed by a rapid electron transfer from the -Re-I(CO)(3)(tmphen)(center dot) to the Fe-III center in the heme to produce ferrocytochrome C, Fe-II-Cyt c. (C) 2009 Elsevier B.V. All rights reserved.