移位错误会毒害密度函数的多体扩张
Dustin R Broderick1, John M Herbert1
1Department of Chemistry & Biochemistry, The Ohio State University 151 W. Woodruff Ave. Columbus Ohio 43210 USA herbert@chemistry.ohio-state.edu.
Chemical science
|November 21, 2024
概括
多体膨胀与密度函数理论相结合,显示了由于自我相互作用错误导致的离子-水相互作用的重大错误. 基于能量的选可以减轻这些问题,但建议对这种量子化学方法保持谨慎.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 物理化学 物理化学
背景情况:
- 多体膨胀 (MBE) 是一种基于碎片的方法,用于大规模的量子化学计算.
- MBE越来越多地用于装配力场和机器学习,特别是用于水和水系统.
- 之前的研究没有突出这些背景下MBE的重大问题.
研究的目的:
- 调查多体膨胀的准确性和局限性,当与离子-水相互作用的半局密度函数理论相结合时.
- 确定错误的来源,并探索潜在的缓解策略.
主要方法:
- 利用了与半局密度函数理论 (DFT) 的多体扩张方法.
- 检查的离子-水相互作用,特别是F-(H2O) N集群,N >= 15.
- 测试了各种缓解策略,包括混合函数,平衡校正,密度校正和介电连续模型.
- 作为一种潜在的解决方案,研究了基于能源的选.
主要成果:
- 半声 DFT 与 MBE 结合,在 N >= 15 个集群的离子-水相互作用中表现出疯狂的振荡和错误积累.
- 在DFT中,自我交互错误被确定为这些不同的行为的主要原因.
- 在小集群中,这些错误是微小的,但在较大的集群中变得灾难性.
- 具有>50%精确交换的混合函数可以抵消错误,但现代的元GGA (ωB97X-V,SCAN,SCAN0) 是不够的.
- 反平衡校正,密度校正和连续模型的有效性有限.
- 基于能量的选成功地防止了不同的行为.
结论:
- 使用离子-水系统的密度函数理论的多体膨胀时需要非常小心.
- 自动交互错误是一个关键问题,可以导致MBE-DFT计算的灾难性失败.
- 基于能源的选提供了一种可行的策略,以提高MBE-DFT对此类系统的可靠性.
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