一个MASH模拟的cyclobutanone的光激发动力学
Joseph E Lawrence1,2,3, Imaad M Ansari1, Jonathan R Mannouch4
1Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland.
The Journal of chemical physics
|May 15, 2024
概括
我们模拟了循环butanone.
科学领域:
- 量子化学是一种量子化学.
- 化学动力学 化学动力学
- 频谱学是一种光谱学.
背景情况:
- 循环butanone光解离是化学动力学研究的一个关键领域.
- 了解非相应动力学对于预测光刺激后的分子行为至关重要.
- 实验研究提供了关于环butanone 分离途径的见解.
研究的目的:
- 为了模拟循环布坦在光激发后到S2状态后的非adiabatic动态.
- 为了预测即将进行的实验的时间分辨率电子衍射信号.
- 为了证明未合球体多态MASH (unSMASH) 方法对初始模拟的适用性.
主要方法:
- 使用地表跳跃 (MASH) 的映射方法模拟非adiabatic动态.
- 采用MASH的多态概括,称为unSMASH,用于三个相关的电子状态.
- 使用状态平均的完整活动空间自相一致场 (CASSCF) 计算,用于ab initio轨迹的 (12,11) 活动空间.
主要成果:
- 在光激发后模拟了第一个500 fs的循环布坦放松.
- 观察到的动态主要由三组离合产物主导:C3H6 + CO,C2H4 + C2H2O,以及C2H4 + CH2 + CO.
- 根据已识别的解离路径解释预测的电子衍射信号.
结论:
- 无SMASH方法适用于复杂的非adiabatic动态的初始模拟.
- 模拟的动态和预测的电子衍射信号为循环butanone光解离提供了宝贵的见解.
- 这项研究作为未来对光化学过程的研究的基准.
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