非对线自旋密度函数理论的自我相互作用校正方案
Nicolas Tancogne-Dejean1,2, Martin Lüders1, Carsten A Ullrich3
1Max Planck Institute for the Structure and Dynamics of Matter and Center for Free-Electron Laser Science, Luruper Chaussee 149, 22761 Hamburg, Germany.
The Journal of chemical physics
|December 12, 2023
概括
我们将密度函数理论的自我相互作用校正 (SIC) 方法扩展到非对线磁系统. 平均密度SIC提高了电离能,而Perdew-Zunger SIC则引入了交换相关扭矩.
科学领域:
- 计算化学是一种计算化学.
- 量子力学就是量子力学.
- 材料科学是一种材料科学.
背景情况:
- 密度函数理论 (DFT) 是一种用于电子结构计算的强大的量子力学方法.
- 自相互作用误差 (SIE) 是标准DFT近似的已知限制,影响某些属性的准确性.
- 非线性磁力包括与特定轴不对齐的磁矩,在分子磁铁和集群中很常见.
研究的目的:
- 扩展已建立的自我相互作用校正 (SIC) 方案,特别是Perdew-Zunger (PZ-SIC) 和平均密度SIC (AD-SIC),以处理具有非对线磁性的系统.
- 评估这些扩展的SIC方案的性能与分子和金属集群系统的局部自旋密度近似值 (LSDA) 相结合.
- 分析由扩展的PZ-SIC产生的交换相关磁场的行为.
主要方法:
- 在DFT框架内对非对线磁系统实施通用的Perdew-Zunger SIC和平均密度SIC.
- 应用这些扩展的SIC方法,结合局部自旋密度近似 (LSDA),以计算所选分子和金属的电子性质.
- 对交换相关性磁场及其与局部总磁化对齐的研究.
主要成果:
- 扩展的AD-SIC方案有效地提高了计算的电离能,与对直线系统的发现一致.
- 扩展的AD-SIC方案显示了精确预测微妙属性的局限性,例如极性分子的双极时刻.
- 由扩展的PZ-SIC产生的交换相关磁场被发现与局部总磁化不一致,导致交换相关扭矩.
结论:
- 开发的SIC方案为DFT中的非线性磁性处理提供了可行的方法.
- AD-SIC对改善电离能有好处,但对其他特性需要进一步精细化.
- 在PZ-SIC中交换相关磁场的错位引入了扭矩,为研究磁现象提供了新的途径.
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