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磁性金属的增强扭曲平均技术:使用量子蒙特卡洛的应用

Abdulgani Annaberdiyev¹, Panchapakesan Ganesh¹, Jaron T Krogel²

¹Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.

Journal of chemical theory and computation

|March 18, 2024

概括

我们开发了一种用于量子蒙特卡洛方法的新扭转平均方案. 这种方法提高了磁性和非磁性材料的总能量和磁性的融合,与实验数据有很好的一致性.

科学领域:

计算物理计算物理
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:

量子蒙特卡洛 (QMC) 方法是电子结构计算的强大工具.
准确的Brillouin区域采样对于金属系统至关重要.
现有的扭转平均 (TA) 方案可能会受到能源波动的影响,需要后期处理.

研究的目的:

为 QMC 方法提出一个改进的扭转平均 (TA) 方案.
加强对磁性和非磁性材料的总能量和磁性的融合.
为了避免能量波动和需要进行后处理纠正.

主要方法:

开发了一个新的TA方案,使用收的Kohn-Sham或Hartree-Fock轨道作为参考.
根据适用于非磁导体的磁性金属的Brillouin区域采样方案进行了定制.
应用的扩散蒙特卡洛 (DMC) 到非磁性 (Al) 和铁磁性α-铁 (α-Fe).

主要成果:

拟议的TA方案表明,总能量和磁力向热力学极限 (TDL) 强地趋同.
通过施工实现电荷中立性,消除大能量波动.
关于Al的DMC计算显示,TDL凝聚能和实验结果之间有很好的一致性.
在α-Fe中的磁矩随着越来越多的扭曲而迅速收.

结论:

改进的TA方案为金属系统的QMC计算提供了更强大,更有效的方法.
它为凝聚性能量和磁性特性提供了准确的结果.
这种方法特别有利于研究磁性材料及其特性.

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