Time-resolved EPR and laser photolysis investigations of photoinduced ω-bond dissociation in an aromatic carbonyl compound having triplet π,π* character
作者:Minoru Yamaji、Susumu Inomata、Satoru Nakajima、Kimio Akiyama、Shozo Tero-Kubota、Seiji Tobita、Bronislaw Marciniak
DOI:10.1016/j.cplett.2005.09.123
日期:2006.1
Photochemical properties of photoinduced ω-bond dissociation in p-phenylbenzoylbenzyl phenyl sulfide (PPS) having the lowest triplet state (T1) of π,π* character in solution were investigated by time-resolved EPR and laser flash photolysis techniques. PPS was found to undergo photoinduced ω-bond cleavage in the excited lowest singlet state (S1(n,π*)) with a quantum yield (Φrad) of 0.15 for the radical
通过时间分辨EPR和激光闪光光解技术研究了溶液中具有π,π*特征的三重态(T 1)最低的对-苯基苯甲酰基苄基苯基硫化物(PPS)中光诱导的ω-键解离的光化学性质。PPS被发现经历光致在最低激发单重态ω-键裂解(S 1(N,π*))与量子产率(Φ弧度为0.15)为自由基形成,这是独立的激发波长。基于观察到的事实,观察到在蒽酮对三联体敏化后三联体PPS的吸收光谱,以及没有CIDEP信号,表明在T 1中不存在ω裂解。PPS的(π,π*)状态。考虑到PPS的激发态和解离态的电子特性,显示了PPS的ω键解离的示意性能量图。