将总KS-DFT交换-关联能量精确分解为一个和两个中心项
Martí Gimferrer1, Pedro Salvador1
1Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, Maria Aurèlia Capmany 69, 17003 Girona, Catalonia, Spain.
The Journal of chemical physics
|June 16, 2023
概括
本研究评估了分解Kohn-Sham密度函数理论 (KS-DFT) 分子能量成原子和二原子部分的两种方法. 这两种方法都显示出类似的性能,其中一种方法很好地与共价键中的电子相关效应保持一致.
科学领域:
- 量子化学是一种量子化学.
- 计算化学是一种计算化学.
- 理论化学是一种理论化学.
背景情况:
- 相互作用量子原子 (IQA) 方法将分子能量分解为原子和二原子的贡献.
- 现有的IQA配方是为Hartree-Fock和后Hartree-Fock方法建立的,但不是Kohn-Sham密度函数理论 (KS-DFT).
研究的目的:
- 批判性地分析两个添加IQA方法对KS-DFT能量分解的性能.
- 为了比较弗朗西斯科等人. 和萨尔瓦多-迈耶IQA (SM-IQA) 方法.
- 在IQA中提出一个新的方案,以最大限度地减少二电子能量计算中的数值错误.
主要方法:
- 应用两个添加IQA方法 (弗朗西斯科等人. 和SM-IQA) 到KS-DFT的能量分解.
- 计算原子和二原子交换相关性 (xc) 的能量组成部分.
- 对包括各种键类型和迪尔斯-阿尔德反应坐标在内的分子测试集的分析.
- 开发一种新的方案,以减少双电子能量贡献中的数值错误.
主要成果:
- 两种评估的IQA方法在KS-DFT能量分解方面表现相似.
- SM-IQA二原子交换相关成分通常比Hartree-Fock值更少负,这与电子相关对共价键的影响一致.
- 详细介绍了一种新的方法,以尽量减少两个电子能量贡献的总和中的数值错误.
结论:
- 这项研究对KS-DFT的IQA方法进行了比较分析.
- 这些发现支持这些IQA方法的适用性,用于分析KS-DFT内的化学键中的电子相关效应.
- 为IQA计算引入了一个新的数值误差最小化方案.
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