Solvent/solute interactions probed by picosecond transient Raman spectroscopy: mode-specific vibrational dynamics in S1 trans-stilbene
Solvent/solute interactions probed by picosecond transient Raman spectroscopy: mode-specific vibrational dynamics in S1 trans-stilbene
复制标题
通过皮秒瞬态拉曼光谱探测溶剂/溶质相互作用：S1 反式二苯乙烯中的模式特定振动动力学
DOI：
10.1021/j100201a047
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
T. Gustafson
中科院分区：
文献类型：
--
作者：
W. Weaver;L. Huston;K. Iwata;T. Gustafson
我们获得了S反式二苯乙烯在乙腈和正己烷中的皮秒瞬时拉曼光谱。我们观察到振动光谱中与模式有关的溶剂依赖的变化。在乙腈中，由于激发态与更极性的溶剂的偶合程度增加，与分子苯基部分有关的S反式二苯乙烯的振动能带相对于正己烷向更高的能量移动和带宽增加。在这两种溶剂中，与分子中的烯烃部分相关的振动运动随着延迟而改变峰位置和带宽，而在每种溶剂中的苯基模的峰位置和带宽随延迟保持不变。烯烃模峰位置和带宽的变化取决于用于激发分子的激发频率。我们将这些变化部分归因于通过涉及低频振动的共振能量交换而产生的振动弛豫。其他因素，可能归因于构象变化，似乎引起了我们观察到的部分影响。参考文献70，图8，表1。
We obtain the picosecond transient Raman spectra of S{sub 1} trans-stilbene in acetonitrile and n-hexane. We observe mode-specific solvent-dependent variations in the vibrational spectra. In acetonitrile, the vibrational bands in S{sub 1} trans-stilbene associated with the phenyl portion of the molecule shift to higher energy and increase in bandwidth, relative to n-hexane, owing to the increased coupling of the excited state to the more polar solvent. In both solvents, the vibrational motions associated with the olefin portion of the molecule change peak position and bandwidth with delay, while the peak position and bandwidths of the phenyl modes in each solvent remain constant with delay. The change in peak position and bandwidth of the olefin modes depends on the excitation frequency used to excite the molecule. We attribute these changes, in part, to vibrational relaxation via resonance energy exchange involving low-frequency vibrations. Additional factors, likely attributable to conformational changes, appear to give rise to a portion of the effects we observe. 70 refs., 8 figs., 1 tab.