Primary photochemical processes for PtCl62− complex in acetonitrile solutions.

Photosolvation of hexachloroplatinate(IV) in acetonitrile with the formation of the Pt IV Cl 5 (CH 3 CN) − complex was studied in the time range from hundreds of femtoseconds to seconds. The primary Pt(III) intermediate was recorded and interpreted as the primary Adamson radical pair [Pt III Cl 5 2‐ (C 4v )⋯Cl ], which then accepts an electron from a solvent molecule. Two successive Pt(III) intermediates recorded in time range from microseconds to tens of milliseconds were interpreted as Pt III Cl 5 2− (C 4V ) and Pt III Cl 4 − complexes. Pt III Cl 4 − was proposed to be a chain carrier in the chain photosolvation process. Dependencies of quantum yield of photosolvation on the initial complex concentration and excited light intensity were fitted in the framework of the proposed chain mechanism. Rate constants of the reactions of intermediates were determined. [ABSTRACT FROM AUTHOR]