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分数电荷的密度函数理论:局部性,尺寸一致性和交换相关性
1Department of Chemistry and Center for Computational and Data Sciences, Middle Tennessee State University, 1301 Main St., Murfreesboro, Tennessee 37130, USA.
The Journal of chemical physics
|December 12, 2024
概括
我们为密度函数引入了i-locality,将精确的通用函数扩展到小数电子电荷. 这使得分数分子的精确计算成为可能,这对于分子研究和计算化学至关重要.
科学领域:
- 量子化学 是一个量子化学.
- 计算物理 计算物理
- 密度函数理论 密度函数理论
背景情况:
- 精确的通用密度函数是电子结构计算的基础.
- 将函数扩展到微分电荷是量子化学的一个长期挑战.
- 分子尺寸的一致性是准确的理论模型的关键原则.
研究的目的:
- 为了将精确的通用密度函数扩展到带有微小电子电荷的系统.
- 在密度函数中引入和探索i-locality概念.
- 建立一个理论框架,准确地描述分数分子.
主要方法:
- 准确的通用密度函数的应用到异面分离的密度.
- 对密度函数和外部潜力的i-locality概念的开发.
- 限制性搜索电子电荷分布在带有分数电子的系统中.
- 对分数分子的非相互作用运动能功能的Kohn-Sham (KS) 分析.
主要成果:
- 精确的通用密度函数,当扩展时,对分数电荷表现出i-locality.
- 介绍了一种在不同位置明确搜索小数电子电荷的方法.
- 分数分子被证明是物理上有意义的,相当于非对称的可分离性.
- 对于分数分子的KS动能函数是明确定义的和i-local.
- 对于分数占用率的新型交换相关函数得到了导出和验证.
结论:
- "i-locality"的概念提供了密度函数的严格扩展到分数电荷.
- 分数分子是分子研究中一个有效和有用的概念.
- 开发的框架准确地描述了带有微小电子电荷的系统,改进了计算化学方法.
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