一种一般方法,用于定位多个旋转状态的旋转禁止反应的混合旋转表面上的静止点
1Institute of Modern Physics, Northwest University, Xi'an, Shaanxi 710127, People's Republic of China.
The Journal of chemical physics
|June 8, 2023
概括
一个新的多态自旋混合 (MSSM) 模型有效地研究涉及多个自旋状态的自旋禁止反应. 该方法使用密度函数理论 (DFT),提供与5d过渡元素相对论计算相比较准确的结果.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 化学物理 化学物理
背景情况:
- 旋转禁止反应涉及旋转倍数的变化,在化学过程中至关重要.
- 旋转轨道合 (SOC) 显著影响了旋转禁止反应.
- 现有的模型,如双状态旋转混合 (TSSM),仅限于两个旋转状态.
研究的目的:
- 引入一种新的多态自旋混合 (MSSM) 模型来研究自旋禁止反应.
- 为MSSM模型开发分析的第一和第二导数.
- 评估MSSM与密度函数理论 (DFT) 结合5d过渡金属反应的性能.
主要方法:
- 开发多态自旋混合 (MSSM) 模型.
- 对MSSM的分析第一和第二衍生品的实施.
- 将MSSM DFT应用于涉及5d过渡元素的旋转禁止反应,并将结果与两组相对论DFT进行比较.
主要成果:
- 与双组件DFT相比,MSSM DFT准确地复制了静止点信息 (结构,频率,零点能量).
- 通过MSSM DFT计算的反应能量与和5d元素的双组件DFT (在3kcal/mol内) 很好地一致.
- 使用双组件DFT进行的后期能量校正进一步提高了不和5d元素的精度,将误差降低到~1kcal/mol.
结论:
- MSSM模型提供了一种有效和计算效率高的方法,用于研究具有多个旋转状态的旋转禁止反应.
- 对于许多系统来说,MSSM DFT为更昂贵的计算相对论方法提供了可靠的替代方案.
- 开发的MSSM方法和相关软件是复杂化学反应理论研究的宝贵工具.
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