Liu Yuzhu, Tang Bifeng, Shen Huan, Zhang Song, Zhang Bing
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan, Hubei 430071, PR China.
Opt Express. 2010 Mar 15;18(6):5791-801. doi: 10.1364/OE.18.005791.
The dynamics of excited states in o-xylene molecules has been studied by femtosecond time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. The ultrafast internal conversion from the S(2) state to the vibrationally hot S(1) state on timescale of 60 fs is observed on real time. The secondarily populated high vibronic S(1) state deactivates further to the S(0) state on timescale of 9.85 ps. Interestingly, the lifetime of the low vibronic S(1) state is much longer, extrapolated to ~12.7 ns. The great differences of lifetime of different vibronic S(1) state are due to their different radiationless dynamics.
通过飞秒时间分辨光电子成像结合时间分辨质谱研究了邻二甲苯分子中激发态的动力学。在60飞秒的时间尺度上实时观察到了从S(2)态到振动激发的S(1)态的超快内转换。二次填充的高振动态S(1)态在9.85皮秒的时间尺度上进一步弛豫到S(0)态。有趣的是，低振动态S(1)态的寿命长得多，外推至约12.7纳秒。不同振动态S(1)态寿命的巨大差异是由于它们不同的无辐射动力学。
