1,2-二乙烯中的超快速光化学过程,用通用XUV探头测量
Henry G McGhee1, Henry J Thompson2, James Thompson3
1Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK. michael.parkes@ucl.ac.uk.
Physical chemistry chemical physics : PCCP
|November 6, 2024
概括
使用时间分辨率光电子谱学研究1,2-二乙烯异构体,揭示了超快的动态. 兴奋状态迅速衰变为基态或产品,受C-C-H曲线的影响.
科学领域:
- 摄影化学的使用.
- 分子光谱学 分子光谱学
- 量子动力学 量子动力学是什么?
背景情况:
- 1,2-二乙烯以cis-和trans-异构体的形式存在.
- 双键周围的异构化可以导致复杂的光化学.
- 了解激发状态动态对于控制化学反应至关重要.
研究的目的:
- 为了研究cis-和trans-1,2-dichloroethene的超快兴奋状态动态.
- 为了观察光刺激后产品的形成.
- 阐明振动模式在兴奋状态衰变路径中的作用.
主要方法:
- 时间分辨率探头光电子光谱学,使用22.3 eV的XUV探头.
- 使用200纳米激光器进行光刺激.
- 支持实验观测的初始计算.
主要成果:
- 在实验时间分辨率 (<70 fs) 内观察到超快的兴奋状态动态.
- 人口转移到产品道发生在同一个超快的时间表上.
- 涉及C-C-H曲线的振动模式被确定为促进兴奋状态人口转移.
结论:
- 1,2-二乙烯的光化学特征是快速激发状态衰变和产物形成.
- 振动动力学在激发分子的非adiabatic过渡中起着至关重要的作用.
- 时间分辨率光电子光谱是一种用于探测超快分子过程的强大工具.
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