复杂的潜在能量表面与预测的CAP技术:N2的振动激发
Soubhik Mondal1, Ksenia B Bravaya1
1Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA.
The Journal of chemical physics
|July 10, 2024
概括
预测复杂吸收电位 (CAP) 技术准确计算了共振能量和宽度. 将CAP与先进的电子结构方法 (如XMS-CASPT2和EOM-EA-CCSD) 结合起来,可以模拟复杂的分子过程.
科学领域:
- 量子化学 是一个量子化学.
- 理论化学 理论化学
- 计算物理 计算物理
背景情况:
- 分子系统中的共振对于理解反应动态至关重要.
- 计算共振能量和宽度通常需要专门的计算技术.
- 预测复杂吸收潜力 (CAP) 方法提供了一种扩展边界状态计算方法的方法.
研究的目的:
- 用不同的电子结构方法与预计的CAP技术相结合,评估生成的潜在能量曲线的准确性.
- 评估这些方法对模拟共振振动激发 (RVE) 过程的性能.
- 对实验数据进行计算结果的验证.
主要方法:
- 应用预测复杂吸收潜力 (CAP) 技术.
- 使用各种电子结构方法计算潜在能量曲线:基于CAP的扩展多态完整的活性空间扰动理论 (XMS-CASPT2),单双替代 (EOM-EA-CCSD) 的电子附着的运动方程合集群方法,单个 (MR-CIS) 和单个和双个 (MR-CISD) 的多参考配置相互作用.
- 使用石模型计算RVE截面.
主要成果:
- XMS-CASPT2和EOM-EA-CCSD方法,当与预计的CAP技术相结合时,可以产生准确的潜在能量曲线.
- 使用这些方法对N2电子冲击进行模拟的RVE截面与实验数据有很好的一致性.
- 对不同电子结构方法的比较凸显了XMS-CASPT2和EOM-EA-CCSD在这种类型的计算中的优势.
结论:
- 预计的CAP技术,当与XMS-CASPT2和EOM-EA-CCSD等精确的电子结构方法相结合时,是动态模拟的可靠方法.
- 这种方法的组合对于研究涉及超稳定电子状态的过程是有效的.
- 该研究验证了使用预测的CAP用于分子系统中准确的共振计算.
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