MECHANISTIC STUDIES OF THE ONE-ELECTRON OXIDATION OF WATER TO HYDROXYL RADICALS PHOTOSENSITIZED BY PERFLUORINATED P-TERPHENYL

Photo-oxidation of water in a system consisting of perfluorinated p-te rphenyl (F-OPP-3) as a photosensitizer, O-2 as an oxidative quencher a nd benzene as a hydroxyl radical scavenger is mechanistically studied by laser flash photolysis and gamma-ray and pulse radiolysis. The radi cal cation of F-OPP-3 (F-OPP3(.+)) is formed via the oxidative quenchi ng of its excited singlet state by O,. The decay of F-OPP-3(.+) observ ed in transient spectroscopy is enhanced by the addition of water to t he system, indicating that F-OPP-3(.+) plays a crucial role in the one -electron oxidation of water.