预测磁性合和旋转极化能量在三角形类型中
Hongde Yu1, Jianwei Sun2, Thomas Heine1,3,4
1Faculty of Chemistry and Food Chemistry, TU Dresden, 01069 Dresden, Germany.
Journal of chemical theory and computation
|June 1, 2023
概括
预测像三角烯这样的无金属磁系统的磁性属性是密度函数理论 (DFT) 的挑战. 这项研究对DFT函数进行了基准测试,发现PBE0,M06-2X和MN15为磁合和旋转极化能量提供了最佳的精度.
科学领域:
- 计算化学是一种计算化学.
- 材料科学是一种材料科学.
- 量子化学是一种量子化学.
背景情况:
- 三角体和相关的无金属磁体系统具有重要的研究兴趣.
- 在这些系统中,由于它们的多参考性质,用标准密度函数理论 (DFT) 难以准确预测磁合和自旋偏振能量.
研究的目的:
- 创建一个25个具有非局部自旋密度的磁系统的基准数据集.
- 为了评估22个常用的DFT函数的性能,用于预测磁性.
- 为无金属磁系统识别可靠的DFT函数.
主要方法:
- 使用完整主动空间自相一致场 (CASSCF) 和合集群方法进行高质量的参考计算.
- 对22个DFT函数与磁合 (J) 和旋转极化能量 (ΔEspin) 的参考数据进行比较.
- 分析不同DFT函数的准确性和可靠性,以预测基本状态电子属性.
主要成果:
- 没有任何DFT函数在所有系统中实现一致的定量准确性.
- PBE0,M06-2X和MN15函数正确预测了所有研究系统的电子基本状态.
- 这三种函数对 ΔEspin 和 J 的平均绝对误差最低,这表明它们适合作为先进方法的起点.
结论:
- 当前的DFT函数很难在没有金属的磁系统中量化预测磁合和旋转极化能量.
- 建议在初步研究中使用PBE0,M06-2X和MN15,因为它们在预测地面状态和磁性特性方面的性能优越.
- 为了获得高度准确的预测,可能需要使用更高级别的方法 (如GW或随机相近似) 进行进一步的研究.
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