迈向无参数的第一步,非局部动能密度对半导体和简单金属具有功能
Abhishek Bhattacharjee1, Subrata Jana2, Prasanjit Samal1
1School of Physical Sciences, National Institute of Science Education and Research, An OCC of Homi Bhabha National Institute, Jatni 752050, India.
The Journal of chemical physics
|June 14, 2024
概括
本研究引入了一种新的,无参数的动能密度函数 (KEDF),使用与间隙模型 (JGM) 内核. 这个JGM内核提高了金属和半导体在无轨密度函数理论计算中的精度.
科学领域:
- 计算物理 计算物理
- 材料科学 材料科学 材料科学
- 量子化学 是一个量子化学.
背景情况:
- 无轨密度函数理论 (OF-DFT) 的准确性依赖于动能 (KE) 函数.
- 当前精确的KE函数使用来自同质电子气体 (HEG) 线性响应理论的非局部内核.
研究的目的:
- 开发一个更准确和更一般的KEE功能,超出HEG近似.
- 引入一种新的非局部KE函数 (NL-KEDF) 基于凝与间隙模型 (JGM).
主要方法:
- 采用了一种密度独立的内核,该内核是从Jellium-with-gap模型 (JGM) 中衍生出来的.
- 开发了一个无参数非局部KE函数 (NL-KEDF).
- 纳入了整体形式主义,将JGM缺口内核集成到现有的基于Lindhard的函数中.
主要成果:
- 在JGM NL-KEDF中,金属和半导体的低动量 (q) 响应函数极限是正确的.
- 证明了JGM NL-KEDF对各种半导体和金属的准确性和效率.
- JGM 内核是密度独立的,并且没有参数.
结论:
- JGM内核为OFF-DFT的NL-KEDF开发提供了更好的预测能力.
- 提出的方法在物理上是合理的,并且在电子结构计算中实际适用.
- 这项工作为更广泛的材料应用增强现有功能提供了一条途径.
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