By using the home-made femtosecond laser system and the time-of-flight mass spectrometer, the decay dynamics of excited carbon disulfide (CS2) and ammonia (NH3) are investigated in real time by pump-probe mul-tiphoton...By using the home-made femtosecond laser system and the time-of-flight mass spectrometer, the decay dynamics of excited carbon disulfide (CS2) and ammonia (NH3) are investigated in real time by pump-probe mul-tiphoton ionization detection. The estimated lifetime constantof the NH3 A1A2 state (51±4 fs) agreed quite well with the literature report. For the first time, the decay lifetime constants of the NH3 E’1A’1, state (937±93 fs), the CS2 a3A2 state (153±10 fs), and the CS2 Rydberg state[3/2](3IIg) (948±23 fs) are obtained.展开更多
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 i...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.展开更多
基金This work was supported by the NationalKey Basic Research Special Foundation of China (Grant No. G1999075300) the National Natural Science Foundation of China (Grant Nos. 29833080, 20003012 and 29973044).
文摘By using the home-made femtosecond laser system and the time-of-flight mass spectrometer, the decay dynamics of excited carbon disulfide (CS2) and ammonia (NH3) are investigated in real time by pump-probe mul-tiphoton ionization detection. The estimated lifetime constantof the NH3 A1A2 state (51±4 fs) agreed quite well with the literature report. For the first time, the decay lifetime constants of the NH3 E’1A’1, state (937±93 fs), the CS2 a3A2 state (153±10 fs), and the CS2 Rydberg state[3/2](3IIg) (948±23 fs) are obtained.
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).
文摘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.
