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费米的黄金规则率表达式,用于转换由于非adiabatic衍生品合在adiabatic基础的转换
Seogjoo J Jang1,2, Byeong Ki Min3, Young Min Rhee3
1Department of Chemistry and Biochemistry, Queens College, City University of New York, 65-30 Kissena Boulevard, Queens, New York, New York 11367, United States.
Journal of chemical theory and computation
|February 13, 2025
概括
这项研究开发了一个一般的费米黄金规则速率表达式非adiabatic过渡,结合非康登效应和振动合精确的分子动力学模拟.
科学领域:
- 化学物理 化学物理
- 理论化学 理论化学
- 量子动力学 量子动力学是什么?
背景情况:
- 在分子动力学中,非反应性过渡是至关重要的,它会影响反应速率和能量转移.
- 现有的费米金律理论通常依赖于康登近似,限制了它们的适用性.
- 需要准确的理论框架来捕捉复杂的振动合和非Condon效应.
研究的目的:
- 为了推导一个一般的费米黄金规则 (FGR) 速率表达式,用于非adiabatic状态之间的adiabatic转换.
- 纳入来自非adiabatic衍生合 (NDC) 和振动移位的非Condon贡献.
- 开发一种封闭形式的FGR速率表达式,用于以线性合波器为模型的系统.
主要方法:
- 一般分子哈密尔顿分析以获得NDC术语.
- 使用原始的增压状态和NDC合的准增压近似.
- 对于波器模型的闭式FGR速率表达式的导数.
- 模型计算和应用到非辐射衰变的青.
主要成果:
- 导出了一个一般的FGR率表达式,用于计算非Condon贡献.
- 该表达式包括二次 NDC 项及其与弗兰克-康登模式的合.
- 除了传统的浴室外,还需要两个额外的浴室光谱密度.
- 模型计算揭示了速率表达式的新特征,通过青衰变分析验证.
结论:
- 导出的FGR率表达式提供了一个更全面的描述非adiabatic转换.
- 包括非康登效应和振动合提高了分子动态的准确性.
- 该理论框架适用于各种涉及非adiabatic动态的化学和物理过程.
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