图形多重和法 (MSM) 密度函数理论 (DFT):在基于DFT的"简单"方法中研究积分的可转移性,以解决多确定性问题的方法
Abraham Ponra1, Carolyne Bakasa2, Anne Justine Etindele3
1Department of Physics, Faculty of Science, University of Maroua, P.O. Box 814, Maroua, Cameroon.
The Journal of chemical physics
|December 27, 2023
概括
本研究介绍了多重和法密度函数理论 (MSM-DFT) 的图形方法,以解决静态和非动态相关性问题. 该方法促进了对配置交互矩阵元素的受过教育的猜测,提高了对具有挑战性的分子系统的DFT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
- 电子结构理论 电子结构理论
背景情况:
- 科恩-沙姆密度函数理论 (DFT) 在动态相关性方面表现出色,但在退化或准退化状态下与静态和非动态相关性作斗争.
- 多重和法 DFT (MSM-DFT) 提供了使用对称性的静态相关性的早期解决方案,但在对称性不足的情况下存在非动态相关性的局限性.
- 准确描述电子相关性对于预测分子性质和反应途径至关重要.
研究的目的:
- 开发MSM-DFT的图形方法,以解决DFT中的非动态相关性限制.
- 为了使在没有对称性的情况下,能够对离对角线的配置交互 (CI) 矩阵元素进行有教育的猜测.
- 提供一个框架,用于将DFT公式转换为波函数公式,使用仅交换的替代品 (EXAN).
主要方法:
- 开发了MSM-DFT的图形方法,以方便与波函数CI进行比较.
- 引入了一个只能交换的替代品 (EXAN) 来将MSM-DFT公式转换为波函数公式.
- 应用图形MSM-DFT和EXAN来建模H2的解离和O2的复数问题.
主要成果:
- 图形方法允许对CI矩阵元素进行教育猜测,即使没有对称性.
- EXAN成功地将MSM-DFT转换为波函数公式,适用于时间依赖的DFT和时间依赖的Hartree-Fock.
- 该方法为H2解离中的非动态相关性和O2.2中的非对称性的合元件提供了合理的近似值.
结论:
- 图形MSM-DFT与EXAN相结合,为将非动态相关性纳入DFT提供了一个有希望的策略.
- 这种方法为开发改进的DFT功能提供了重要的限制.
- 该方法表明,在具有强烈静态和非动态相关性的系统中,有可能提高电子结构计算的准确性.
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