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积极学习高维可转移的哈伯德U和V参数在DFT+U+V方案中
Wei Yu1, Zhaofu Zhang2, Xuhao Wan1
1School of Electrical Engineering and Automation, Wuhan University, Wuhan 430072, China.
Journal of chemical theory and computation
|September 14, 2023
概括
使用脱落 (BOD) 算法的贝叶斯优化有效地优化了Hubbard U 和 V 术语用于密度函数理论 (DFT) + U + V 计算. 这种方法提高了散装材料,表面和接口的精度和效率.
科学领域:
- 计算材料科学科学 计算材料科学
- 量子化学 是一个量子化学.
- 固态物理 固态物理
背景情况:
- 密度函数理论 (DFT) 对材料电子结构计算至关重要.
- 实现DFT方法的准确性和效率仍然是一个挑战.
- DFT + U + V 方法提供了更好的准确性,但需要精确的 Hubbard U 和 V 参数.
研究的目的:
- 开发一种高效准确的方法来确定Hubbard U 和 V 参数在 DFT + U + V 计算中.
- 研究U和V参数在不同材料系统 (散装,表面,接口) 中的可转移性.
- 在大型系统中提高电子属性预测的计算效率.
主要方法:
- 使用掉落 (BOD) 算法来优化U和V项的贝叶斯优化实现.
- 对各种散装材料,表面板块和接口应用BOD.
- 将BOD结果与传统的线性响应方法和混合函数进行比较.
主要成果:
- BOD优化了U和V项,为散装材料提供了改进的电子特性,精度与混合功能相比,但计算成本较低.
- 从批量计算中获得的初始U/V参数显示,对板块/接口的可转移性有限.
- 将BOD扩展到板块/接口,实现类似的准确性,并证明U/V参数在系统之间具有合理的可转移性.
结论:
- 使用dropout算法的贝叶斯优化为确定DFT + U + V参数提供了一种高效和准确的方法.
- 开发的方法增强了对散装材料,表面和接口的电子性质的预测.
- 在不同的材料尺度和配置中证明了U / V参数的可转移性,使复杂系统的分析更快.
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