Dynamics of excited m-dichlorobenzene  

作　　者：YUAN Liwei WANG Yanqiu WANG Li BAI Jiling HE Guozhong 

机构地区：[1]State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China

出　　处：《Science China Chemistry》2004年第4期283-288,共6页中国科学(化学英文版)

基　　金：This work was supported by the National Key Basic Research Special Funding Project(Grant No.G1999075301);the National Natural Science Foundation of China(Grant No.20273072);the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.K2002F2).

摘　　要：Dynamics of excited m-dichlorobenzene is investigated in real time by femtosecond pump-probe method, combined with time-of-flight mass spectrometric detection in a supersonic molecular beam. The yields of the parent ion and daughter ion C6H4Cl+ are examined as a func-tion of the delay between the 270 and 810 nm femtosecond laser pulses, respectively. The life-time of the first singlet excited state S1 of m-dichlorobenzene is measured. The origin of this daughter ion C6H4Cl+ is discussed. The ladder mechanism is proposed to form the fragment ion. In addition, our experimental results exhibit a rapid damped sinusoidal oscillation over interme-diate time delays, which is due to quantum beat effects.Dynamics of excited m-dichlorobenzene is investigated in real time by femtosecond pump-probe method, combined with time-of-flight mass spectrometric detection in a supersonic molecular beam. The yields of the parent ion and daughter ion C6H4Cl+ are examined as a function of the delay between the 270 and 810 nm femtosecond laser pulses, respectively. The lifetime of the first singlet excited state S1 of m-dichlorobenzene is measured. The origin of this daughter ion C6H4Cl+ is discussed. The ladder mechanism is proposed to form the fragment ion. In addition, our experimental results exhibit a rapid damped sinusoidal oscillation over intermediate time delays, which is due to quantum beat effects.

关 键 词：FEMTOSECOND lifetime of excited state PUMP-PROBE ionization-dissociation quantum beat 

分 类 号：N[自然科学总论]