超快速兴奋状态动态的trans-4-nitrostilbene的溶剂极性依赖性
Peng-Yun Wang1, Yu-Cheng Hsu1, Pin-Hsun Chen1
1Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 30043, Republic of China. pycheng@mx.nthu.edu.tw.
Physical chemistry chemical physics : PCCP
|December 13, 2023
概括
转-4-尼托基 (t-NSB) 的兴奋状态动态对溶剂极性非常敏感. 它的S1状态寿命有很大的变化,从极性溶剂中的皮秒到非极性溶剂中的秒,影响放松通路.
科学领域:
- 摄影化学的使用.
- 超快速光谱法 超快速光谱法
- 计算化学计算化学
背景情况:
- 酸是一种具有有趣光化学性质的分子类.
- 了解激发状态动态对于控制光化学反应至关重要.
- 已知溶剂极性会影响分子激发状态的寿命和通路.
研究的目的:
- 为了研究转-4-尼托基 (t-NSB) 的超快兴奋状态动态.
- 为了阐明溶剂极性的影响t-NSB的兴奋状态失活.
- 为了将光谱观测与量子化学计算结果相关联.
主要方法:
- 超快速宽带时间分辨率光谱学.
- 超快的宽带短暂吸收光谱.
- 量子化学计算 量子化学计算
主要成果:
- 随着溶剂极度的下降,t-NSB的S1状态寿命减少了三次数 (在高极度溶剂中≤60 ps,在非极性溶剂中≤60 fs).
- 溶剂极性调节相对能量和系统间交叉 (ISC) 速率,这是由于双极时刻的差异造成的.
- 在非极性溶剂中,快速衰变是通过ISC和内部转换;在极性溶剂中,衰变是通过穿越障碍物到垂直配置.
结论:
- t-NSB的兴奋状态动态强烈依赖于溶剂极性.
- 系统间交叉 (ISC) 速率受到溶剂极性的影响,遵循中极性溶剂的逆能量差距定律.
- 最终,激发状态填充了一个转移稳定的T1状态,导致基态产物 (变态或态同体).
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