通过局部混合功能来正确处理核心属性
Matthias Haasler1, Toni M Maier2, Martin Kaupp1
1Technische Universität Berlin, Institute of Chemistry Theoretical Chemistry/Quantum Chemistry, Berlin, Germany.
Journal of computational chemistry
|August 28, 2023
概括
新的局部混合功能 (LHs) 增强了核心区域.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 材料科学 材料科学 材料科学
背景情况:
- 局部混合函数 (LHs) 使用局部混合函数 (LMF) 来定义精确交换的添加剂.
- 现有的LH,如LH20t,在值区域表现出高精度.
- 核心电子区域的准确建模仍然是计算化学的一个挑战.
研究的目的:
- 开发新的局部混合功能 (LHs),在核心电子区域提高精度.
- 为了保持或增强在价值区域的现有函数的高精度.
- 引入新的Padé形式局部混合函数 (pt-LMFs),以更好地近似核心区域.
主要方法:
- 基于帕德近似的新pt-LMFs的开发.
- 使用密度依赖的权力,修改·维茨泽克和科恩-沙姆运动能量的比率.
- 使用TDDFT计算对K-shell核心激发的LMF核心部分的优化.
- 包括相对论轨道修正以提高准确性.
- 校准功能,以最大限度地减少非动态的关联效应.
- 纳入了B95c元-GGA相关性.
主要成果:
- 与LH20t相比,新的LH23pt功能显示了核心区域的特定改进.
- pt-LMFs能够更好地接近高密度和单轨道极限.
- 实现了对第二和第三周期元素的K-shell核心激发的准确建模.
- 保持或改善LH20t的价值区域精度.
结论:
- 开发的LH23pt功能为准确描述核心电子区域提供了重大进步.
- 新的pt-LMF方法为改善LHs提供了一种灵活有效的策略.
- 这些发现有助于更准确的量子化学计算,特别是对于核心相关现象.
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