【作者】 潘洋； 俞书勤；

【Author】 PAN Yang YU Shuqin (Laboratory of Bond-selective Chemistry, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026)

【机构】 中国科学技术大学化学物理系中国科学院选键化学重点实验室；

【Abstract】 Photoinduced electron transfer reactions of N,N,N’, N’- tetramethylbenzidine (TMB) with several electron poor olefins in acetonitrile solution have been studied by using laser flash photolysis and steady-state fluorescence quenching method. The triplet state of TMB which located at 480 nm was found to undergo reductive quenching with the electron acceptors fumaronitrile, dimethyl fumarate, cinnamonitrile, crotononitrile and diethyl fumarate. The detection of ion radical intermediates in the photolysis reactions confirms the proposed electron transfer mechanism, as expected from thermodynamics. The quenching rate constants of triplet TMB have been determined at 510 nm, where all the kq values approach or T reach to diffusion controlled limit. In addition, fluorescence quenching rate constant kq have been also obtained by calculating with Stern-Volmer equation.更多还原