A Time-resolved EPR Study of One- and Two-Photon Processes in the Photochemical Reactions of Benzil

Article abstract of DOI:10.1021/j100348a009

A time-resolved EPR study of the photochemical reactions of benzil in isopropyl alcohol and a benzene-triethylamine (TEA) mixed solvent is reported.Emissive and absorptive chemically induced dynamic electron polarization signals of the intermediate radicals were observed in these two systems.The observed radicals are assigned as the benzoyl and benzil ketyl radicals in the former case and the benzil anion in the latter case.It is found that these photochemical reactions occur from the higher excited triplet state through a two-photon process in isopropyl alcohol and from the lowest excited triplet state through a one-photon process in the benzene-TEA mixed solvent, respectively.