集群扰动理论. 集群扰动理论. 十一. 十一. 十一. 十一. 十一. 激发-能量系列使用一个变化的激发-能量函数
Andreas Erbs Hillers-Bendtsen1, Magnus Bukhave Johansen1, Theo Juncker von Buchwald1,2
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK 2100 Copenhagen Ø, Denmark.
The Journal of chemical physics
|January 9, 2025
概括
我们引入了一种新的方法来计算激发能在合集群 (CC) 理论中的激发能作为一个分子属性,导致两个新的扰动序列. 变化的集群扰动 (vCP) 系列显示了分子激发能量的卓越准确性.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 理论化学 理论化学
背景情况:
- 结合集群 (CC) 理论中的激发能量传统上依赖于解决CC雅可比特自值方程.
- 这项研究建立在最近的工作基础上,重新制定了激发能量的计算.
研究的目的:
- 提出一种新的方法来计算激发能作为一种传统的分子性质.
- 引入激发能函数和拉格朗日方程用于变量计算.
- 开发和评估新的激发能量系列.
主要方法:
- 引入了一个依赖于CC的激发能量函数,雅可比安和自身向量.
- 制定了一种激发能量拉格朗的方程,其中包含了集群振幅方程.
- 衍生出两个二次趋同的激发能量序列:总顺序集群扰动 (tCP) 和变化集群扰动 (vCP).
主要成果:
- 拉格朗的变量属性使得tCP和vCP系列的导出成为可能.
- 对三种小分子的计算表明,对vCP系列的偏好超过tCP.
- vCP系列实现了高精度,与参考CC值平均偏差为~0.04 eV (S(D) 空间) 和0.001 eV (SD(T) 空间.
结论:
- 拟议的方法提供了一个可变的方法来计算CC理论中的激发能.
- 变化的集群-扰动 (vCP) 系列提供了准确的激发能量与二次收.
- 这种重构提供了一个有希望的替代方案,以传统的雅可比特本值方程方法.
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