用导数信息训练机器学习泛函,显著提升能量精度与计算效率。
Derivative Informed Learning of Exchange-Correlation Functionals

- 引入DI-Loss损失函数,监督能量在密度矩阵流形上的导数响应。
- 总能平均绝对误差降低66%,密度敏感能量指标从1.2降至0.8 mEh。
- 生成的密度可减少50%杂化泛函自洽迭代,提升激发态预测精度。
机器学习交换关联(XC)泛函旨在直接从参考数据中学习,替代人工设计的密度泛函近似,但尚未稳定超越传统$\mathcal{O}(N^4)$复杂度的杂化泛函。本文研究了一种混合蒸馏设置,即用$\mathcal{O}(N^3)$复杂度的机器学习XC泛函拟合B3LYP/def2-SVP参考结果。提出导数信息感知的XC损失(DI-Loss),通过监督能量在允许密度矩阵流形上的第一阶和第二阶导数,使学习泛函的局部响应与目标泛函一致。相比仅依赖能量和密度监督,四种架构下总能平均绝对误差(MAE)平均下降66%;密度敏感的平均场能量指标$E_ρ$从1.2降至0.8 mEh,而偶极矩和$\mathcal{L}_2$密度误差未普遍改善。此外,蒸馏得到的密度可使杂化泛函自洽场迭代减少高达50%。下游时间依赖密度泛函理论(TDDFT)计算中,哈密顿量监督使激发态预测更优,XCdiff将平均激发能绝对误差降低19–35%。
原文摘要 · Abstract (English)
Machine-learned (ML) exchange-correlation (XC) functionals aim to replace human-designed density functional approximations by learning directly from reference data, but they still do not consistently outperform traditional $\mathcal{O}(N^4)$-scaling hybrid functionals. We study a hybrid-distillation setting in which $\mathcal{O}(N^3)$-scaling ML-XC functionals are trained to reproduce B3LYP/def2-SVP targets. We introduce Derivative Informed XC-Loss (DI-Loss), a loss that incorporates additional information from the reference hybrid functional by supervising first and second derivatives of the energy on the Grassmannian of admissible density matrices. Rather than only matching the self-consistent fixed point, DI-Loss aligns the local first- and second-order response of the learned functional with that of the target functional. Across four evaluated architectures, DI-Loss consistently improves the main energy metrics. Averaged uniformly across architectures, the total-energy MAE decreases by 66% relative to energy and density supervision alone. The density-sensitive mean-field energy metric $E_ρ$ improves from $1.2$ to $0.8$ mEh on average, while dipole and $\mathcal{L}_2$ density errors do not improve uniformly. We further show that densities from the distilled functionals reduce hybrid-functional SCF iterations by up to 50%. In downstream TDDFT calculations, Hessian supervision improves excited-state predictions, with XCdiff reducing the mean excitation-energy MAE by 19 - 35%.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。