比较密度的功能理论 在二核过渡金属复合体中研究磁交换合的研究
Henry C Fitzhugh1, James W Furness1, Mark R Pederson2
1Department of Physics and Engineering Physics, Tulane University, New Orleans, Louisiana 70118, United States.
Journal of chemical theory and computation
|August 15, 2023
概括
在过渡金属复合体中准确预测磁交换合 (J) 对于开发新的磁性材料至关重要. 对于这些复杂的系统,SCAN和r2SCAN元GGA表现有前途,性能与全球混合物相美.
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.
- 磁力学 磁力学 是一种
背景情况:
- 具有磁离子的多中心过渡金属复合体 (MCTM) 对信息技术具有前景.
- 对于MCTM应用来说,对同源磁交换合器 (J) 的准确表征至关重要.
- 密度函数理论 (DFT) 是用于在大型MCTM中评估J的主要计算方法.
研究的目的:
- 评估各种密度函数近似 (DFAs) 的准确性,以预测磁交换合 (J).
- 为了评估全球混合物,本地混合物,SCAN,r2SCAN元GGA和PBE GGA的双核过渡金属复合体.
- 分析电荷密度再分配及其与自我相互作用或移位错误的关系.
主要方法:
- 用于磁性合预测的DFT函数的计算评估.
- 测试了八个双核过渡金属复合体,具有实验性的J值.
- 对选定的DFA进行电荷密度再分配的分析.
主要成果:
- 与PBE GGA相比,全球混合功能经常过度纠正磁联错误.
- 当地混合功能没有显著改善,缺乏明确的趋势.
- 扫描和r2SCAN元GGA的性能相当于全球混合体的基准测试.
- 分析将电荷密度的变化与自我相互作用/移位错误联系起来.
结论:
- 在J计算中,SCAN和r2SCAN元GGA为全球混合物提供了可行的替代方案.
- 对于预测磁性合的局部混合功能,需要进一步开发.
- 了解电荷密度再分配在磁性特性的DFA性能分析中的帮助.
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