电子在非紧的共价键中的定位,通过r2SCAN+V方法捕获
Yubo Zhang1, Da Ke1, Rohan Maniar2
1Minjiang Collaborative Center for Theoretical Physics, College of Physics and Electronic Information Engineering, Minjiang University, Fuzhou, Fujian 350108, China.
概括
密度函数理论函数SCAN和r2SCAN显示出有希望的结果,但与非紧的共价键相斗争. 一种新的r2SCAN+V方法提高了这些具有挑战性的材料的准确性.
科学领域:
- 计算材料科学 计算材料科学
- 量子化学是一种量子化学.
- 固态物理 固态物理
背景情况:
- 密度函数理论 (DFT) 函数如SCAN和r2SCAN为材料属性提供了比GGA函数的改进.
- 然而,SCAN在特定情况下表现不佳,包括石墨烯带结构和过渡金属的磁时刻.
研究的目的:
- 确定某些材料中SCAN/r2SCAN性能不足的根本原因.
- 提出一个修改后的功能,提高在更广泛的材料类型的精度.
主要方法:
- 在SCAN/r2SCAN失败的具有挑战性的材料中分析电子结构和粘合特性.
- 对r2SCAN+V功能修改的开发和测试.
主要成果:
- 表现不佳的病例的一个共同特征是通过s-s,p-p或d-d杂交的非紧共价键.
- SCAN/r2SCAN可以准确地描述局部电子,但无法在非紧键中的非局部电子.
- 通过r2SCAN+V方法,所有测试材料的精度都提高了,材料依赖的参数是V.
结论:
- 非紧的共价键是当前基于SCAN的函数的关键挑战.
- 功能性r2SCAN+V提供了一个实际的解决方案,用于提高DFT计算的准确性.
- 这项工作为开发下一代DFT功能提供了指导.
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