在原子和二聚体中,对称性破坏和自我相互作用校正
Rohan Maniar1, Kushantha P K Withanage2, Chandra Shahi1
1Department of Physics and Engineering Physics, Tulane University, 6400 Freret St., New Orleans, Louisiana 70118, USA.
The Journal of chemical physics
|April 8, 2024
概括
密度函数近似中的自我相互作用校正 (SIC) 对于强度相关的系统 (如模) 可以进行过度校正,从而导致非物理结果. 研究人员发现,一个完全的SIC到LSDA会产生一种非物理的对称性破裂状态,这表明SIC需要缩小规模.
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:
- 密度函数近似 (DFAs) 对于研究电子相关性至关重要.
- 强烈相关的系统,如二元体,对DFAs构成挑战.
- 对称性破坏是DFA描述这些系统的关键机制.
研究的目的:
- 为了研究自我相互作用校正 (SIC) 对二元体的影响.
- 为了评估完整的Perdew-Zunger SIC应用到局部旋转密度近似 (LSDA) 的准确性.
- 了解电子结构计算中非物理对称性破坏的含义.
主要方法:
- 使用密度函数近似,特别是LSDA和PBE-GGA.
- 对LSDA进行了完整的Perdew-Zunger自我相互作用校正 (SIC).
- 分析了二元体和分离的原子的结合能曲线和电子配置.
主要成果:
- LSDA和PBE-GGA在质量和数量上描述了二极体的结合曲线与反铁磁对称性破坏.
- 一个完整的Perdew-Zunger SIC到LSDA会导致一个非物理的对称性破裂状态,显著降低总能量.
- 这种非物理状态表现出零磁矩但非零原子自旋密度,二元体的能量超过了分离的原子的能量.
结论:
- 完全SIC到LSDA对二元体进行过度校正,导致非物理电子状态.
- 这些发现表明,SIC方法可能需要在具有显著电子相关性的区域缩小规模.
- 这项工作为完善电子结构理论中的SIC实现提供了定性证据.
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