Ultrafast Electronic Relaxation and Hydrogen-Bond-Formation/Dissociation Dynamics of Photoexcited All-trans Retinal in Protic Solvents
Ultrafast Electronic Relaxation and Hydrogen-Bond-Formation/Dissociation Dynamics of Photoexcited All-trans Retinal in Protic Solvents
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质子溶剂中光激发全反式视黄醛的超快电子弛豫和氢键形成/解离动力学
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发表时间：
2000
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影响因子：
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通讯作者：
H. Hamaguchi
中科院分区：
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作者：
Shoichi Yamaguchi and;H. Hamaguchi
利用飞秒时间分辨可见吸收光谱研究了光激发全反式视黄醛在正丁醇/环己烷混合溶剂中的超快电子弛豫和氢键形成/解离动力学.四个瞬态吸收带，这可以分配给S3，S2，S1和T1状态，观察到在纯环己烷。这些吸收带的形状和动力学与以前报道的全反式视黄醛在己烷中的那些非常一致。相比之下，只有三个瞬态吸收带，这可以被分配到S3，S2和T1状态，被确定在混合溶剂中。分配给S2状态的频带显示出依赖于时间的峰位移，这是由于溶剂重组的皮秒时间尺度。对三个瞬态吸收带的动力学分析表明，在氢键形成时，激发态单重态中（n，π*）和（π，π*）态的态序没有发生变化。1-bu.
The ultrafast electronic relaxation and the hydrogen-bond-formation/dissociation dynamics of photoexcited all-trans retinal in 1-butanol/cyclohexane mixed solvents have been studied by femtosecond time-resolved visible absorption spectroscopy. Four transient absorption bands, which can be assigned to the S3, S2, S1, and T1 states, were observed in neat cyclohexane. The shapes and the dynamics of these absorption bands agree very well with those reported previously for all-trans retinal in hexane. In contrast, only three transient absorption bands, which can be assigned to the S3, S2, and T1 states, were identified in the mixed solvents. The band assigned to the S2 state showed a time-dependent peak shift, which is attributed to solvent reorganization on a picosecond time scale. A kinetic analysis of the three transient absorption bands has led to the conclusion that no state-ordering change of the (n, π*) and (π, π*) states takes place in the excited singlet manifold upon hydrogen-bond formation. The 1-bu...