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旋转交叉材料的过渡温度与平均值组合 Hubbard-U 校正

Angel Albavera-Mata^1,2, Richard G Hennig^1,2, S B Trickey^1,3

¹Center for Molecular Magnetic Quantum Materials, Quantum Theory Project, University of Florida, Gainesville, Florida 32611, United States.

The journal of physical chemistry. A

|September 5, 2023

概括

计算旋转交叉过渡温度 (T1/2) 是复杂的. 这项研究改进了使用Hubbard-U校正和近似方法的方法,通过成本有效的密度功能理论来实现材料选的准确结果.

科学领域:

计算化学计算化学
材料科学材料科学材料科学
固态物理固态物理

背景情况:

在冷凝相中精确计算旋转交叉 (SCO) 过渡温度 (T1/2) 在计算上具有挑战性.
准确的亚流动交叉能量差异 (ΔE_HL) 和贡献对于预测SCO行为至关重要.
现有的密度函数近似 (DFA) 难以平衡SCO材料的精度和计算成本.

研究的目的:

调查哈伯德-U校正和贡献对SCO热化学性质的影响.
开发一种计算效率高,准确的方法来计算SCO材料的T1/2.
通过将低计算成本与可靠的预测相结合,使SCO材料的高通量选成为可能.

主要方法:

采用了从20个SCO材料的参考集合旋转状态中获得的Hubbard-U校正.
使用了第一个协调球的近似方法,并假定外部原子的类似振动贡献.
比较了PBE通用梯度DFA与r2SCAN元通用梯度DFA的性能.

主要成果:

哈伯德-U校正,特别是从简单的表示,可以过度纠正 ΔE_HL,导致减少 T1/2 值.
使用PBE-DFA的拟议方法实现了T1/2结果,与计算成本更高的r2SCAN DFA相美.
简化方法有效地捕捉了SCO材料的基本热化学特性.

结论:

结合PBE-DFA与特定近似和Hubbard-U校正的计算效率高的方法使得准确的T1/2预测成为可能.
这种方法为旋转交叉材料的高通量计算选提供了一个有希望的途径.
这些发现减少了对SCO材料表征的计算密集型方法的依赖.

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