多配置对密度功能理论比你想象的要复杂得多.
Gabriel L S Rodrigues1, Mikael Scott1, Mickael G Delcey2
1Division of Theoretical Chemistry and Biology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
The journal of physical chemistry. A
|October 27, 2023
概括
这项研究揭示了将虚构组件纳入多配置对密度函数理论 (MC-PDFT) 计算中的必要性. 结合这个组件可以提高描述电子相关性的准确性,特别是在具有挑战性的分子系统中.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学的计算化学
- 理论化学 理论化学
背景情况:
- 多配置对密度函数理论 (MC-PDFT) 为建模强大和动态电子相关性提供了一种具有成本效益的方法.
- 标准的旋转密度函数通常适用于MC-PDFT,可能会在旋转密度中引入非物理的虚构组件.
- 当前的MC-PDFT方法通常会抛弃这些虚构组件,从而限制它们的准确性.
研究的目的:
- 在MC-PDFT中调查虚构元件在翻译自旋密度中的物理意义.
- 开发和验证一种形式主义,将虚构组件纳入改进的电子结构计算.
- 评估这种形式主义对描述具有挑战性的电子相关性场景的影响.
主要方法:
- 在MC-PDFT中开发了一个形式主义,包括转化自旋密度的非零虚构组成部分.
- 将新形式主义应用于局部密度近似 (LDA) 和通用梯度近似 (GGA) 函数.
- 该方法使用有机二极根和有机分子激发状态的单元-三元 (ST) 间隙进行了基准测试.
主要成果:
- 包含虚构组件对于准确复制物理行为至关重要,特别是在低旋转的开系统中.
- 与忽略虚构部分的现有方法相比,开发的MC-PDFT方案显示了更好的准确性.
- 即使使用最小的活跃空间,也可以获得准确的结果,突出显示了该方法的效率.
结论:
- 翻译自旋密度的虚构组成部分在物理上是相关的,并且对于准确的MC-PDFT计算至关重要.
- 新的MC-PDFT形式主义提供了更强大,更准确的电子相关性描述.
- 这一进步为更可靠的计算化学研究带来了希望,特别是对于具有复杂电子结构的系统.
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