关于电子激发型二氧化物-N-氧化物的超快衰变动态的见解
Baihui Feng1,2,3, Wenping Wu1,3, Shuaikang Yang1,4
1State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning 116023, China. yangdy@dicp.ac.cn.
Physical chemistry chemical physics : PCCP
|February 23, 2024
概括
使用秒光电子成像研究了二氧化的超快衰变动态. 寿命从fmtoseconds到picoseconds变化,取决于激发波长和电子状态,揭示了复杂的失活路径.
科学领域:
- 物理化学 物理化学
- 分子动力学分子动力学
- 摄影化学的使用.
背景情况:
- 胺-N-氧化物是各种化学过程中的关键分子.
- 了解它的兴奋状态动态对于控制光化学反应至关重要.
研究的目的:
- 为了研究光刺激后的比里丁-N-氧化物的超快衰变动态.
- 为了确定不同兴奋状态的生命周期和失活路径.
主要方法:
- 五秒钟时间分辨率的光电子成像技术.
- 激发在近紫外线范围内 (340.2217.6 nm).
- 对时间解析的光电子光谱和角分布的分析.
主要成果:
- 刺激到S1(1ππ*) 状态显示了振动依赖性,寿命从1.4160 ps.
- 激发到第二个1ππ*状态导致超快的衰变 (~60 fs).
- 激发到3秒的瑞德伯格状态,寿命为0.552.2 psi.
结论:
- 这项研究提供了对二氧化N-氧化物的激发状态衰变的全面了解.
- 不同的兴奋状态表现出不同的寿命和失活机制.
- 振动能量和模式显著影响S1状态的人口减少率.
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