Separability of Intra- and Intermolecular Vibrational Relaxation Processes in the S1 State of trans-Stilbene
Separability of Intra- and Intermolecular Vibrational Relaxation Processes in the S1 State of trans-Stilbene
复制标题
反式二苯乙烯S1态分子内和分子间振动弛豫过程的可分离性
DOI：
10.1021/jp962454h
复制
发表时间：
1997
影响因子：
2.9
通讯作者：
J. Jean
中科院分区：
文献类型：
--
作者：
S. L. Schultz;J. Qian;J. Jean
详细的时间分辨测量的反斯托克斯强度的几个高频模式的电子激发的反式二苯乙烯在己烷和甲醇的报告。在1570 cm-1处的烯键谱带中观察到最显著的变化。在v = 1水平的这种模式的非平衡人口被发现表现出一个两相衰减，这被解释为一个快速的能量再分配，然后由一个稍微慢的过程，反映了多余的能量转移到溶剂。将几个高频带随时间变化的强度变化与假设激发态瞬时热化的模型进行比较，表明溶质-溶剂热平衡过程的时间尺度上的内能随机化是不完整的。没有证据的模式特异性的能量再分配过程中观察到。结果表明，我们把一个值的寿命的v = 1水平上的乙烯伸缩模式的反式二苯乙烯在己烷...
Detailed time-resolved measurements of anti-Stokes intensities of several high-frequency modes of electronically excited trans-stilbene in hexane and methanol are reported. The most striking changes are observed in the ethylenic band at 1570 cm-1. Nonequilibrium population in the v = 1 level of this mode is found to exhibit a biphasic decay, which is interpreted as a rapid energy redistribution followed by a slightly slower process that reflects the transfer of excess energy to the solvent. Comparison of the time-dependent intensity changes of several high-frequency bands with those from a model that assumes instantaneous thermalization of the excited state suggests that internal energy randomization is incomplete on the time scale of solute−solvent thermal equilibration process. No evidence of mode specificity in the energy redistribution process is observed. The results show us to place a value of ∼2 ps on the lifetime of the v = 1 level of the ethylenic stretching mode of trans-stilbene in both hexane ...