显著的同位素效应来自于Cl (P) + HD (v) = 0, (j) = 0 中的非合性合
Ransheng Wang1,2, Haimei Shi1,2, Ting Xie1
1State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
The journal of physical chemistry. A
|April 22, 2024
概括
非Born-Oppenheimer合物在Cl + HD反应中显著影响同位素效应. 阿迪亚巴特模型高估了反应性,强调了在量子动力学计算中需要谨慎.
科学领域:
- 化学物理 化学物理
- 量子化学 是一个量子化学.
- 反应动力学 反应动力学
背景情况:
- 研究化学反应中的同位素效应对于理解反应机制至关重要.
- 非Born-Oppenheimer (非adiabatic) 合在动力学中起着重要作用,特别是在具有开特征的系统中.
研究的目的:
- 调查非Born-Oppenheimer合对Cl + HD反应中同位素效应的影响.
- 为了比较非adiabatic量子散射方法的准确性与简单的adiabatic模型.
主要方法:
- 开发并应用了六态和两态非adiabatic时间独立的量子散射模型.
- 在非adiabatic模型中包含全部和部分开特征.
- 计算了反应使用一个简单的亚亚巴特模型与最低的亚亚巴特潜在能量表面.
主要成果:
- 基模型显著高估了Cl + HD → HCl + D通道的反应性.
- 其他通道的活性在非adiabatic和adiabatic模型之间很好地一致.
- 非adiabatic合物大大改变了反应物通道中的范德瓦尔斯井.
结论:
- 简单的亚亚巴特模型可以导致反应动态和同位素效应的显著偏差.
- 对于在某些反应中准确预测,非附加的量子力学计算是必不可少的.
- 在采用非Born-Oppenheimer效应影响的反应时,建议谨慎使用基模型.
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