Photolysis of methylcobalamin. Nature of the reactive excited state
نویسندگان
چکیده
Photolysis of methylcobalamin (Co”‘corrin(CH,)L + Hz0 + Oz + Co”‘(H,O)L + H,CO + OH-) shows a pronounced wavelength dependence. It is suggested that the reactive excited state is of the ligand-to-ligand charge transfer (LLCT) type and involves the promotion of an electron from the Co-C u-bond to a r*(corrin) orbital. This LLCT transition mixes with the 7;z-*(corrin) transitions. Owing to this LLCT contribution, the rrr*-absorption bands are also photoactive hut with reduced efficiency.
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