发表机构
Joint Center for Quantum Information and Computer Science, University of Maryland; Department of Mathematics, University of Maryland; Department of Chemistry and Biochemistry, University of Maryland; Institute for Physical Science and Technology, University of Maryland（马里兰大学量子信息与计算机科学联合中心; 马里兰大学数学系; 马里兰大学化学与生物化学系; 马里兰大学物理科学与技术研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出平滑截断库仑（sTC）势，用于周期高斯基组Hartree-Fock交换计算，可改善热力学极限收敛，适用于多种体系的全电子计算，兼具实用性与精度。
AI 中文摘要
截断库仑（TC）势可减少周期Hartree-Fock（HF）计算中的有限尺寸误差并加速热力学极限收敛，但将其与高斯基组结合使用时，电子排斥积分（ERI）的评估会带来复杂问题，尤其是对于非球形截断域和全电子计算。我们提出平滑截断库仑（sTC）势，作为母TC势的可系统改进近似。实空间高斯卷积对尖锐的截断边界进行平滑处理，单个无量纲参数η控制平滑窗口的宽度，可通过收紧该宽度系统地逼近TC参考。sTC的平滑特性使双空间算法可用于评估周期高斯基组ERI，该算法既不需要大的平面波基组，也不需要新的分子积分核，且适用于赝势和全电子计算，包括重要的Wigner-Seitz晶胞截断边界。涵盖绝缘体、半导体、层状、金属和分子晶体体系的基准测试表明，基于sTC的HF在赝势计算中可紧密重现TC结果，并将TC质量的计算扩展到全电子设置。在这些体系中，sTC相对于探针电荷Ewald方法显著改善了热力学极限收敛，同时对于直接基于TC的计算在计算上具有挑战性的全电子计算仍保持实用性。
英文摘要
Truncated Coulomb (TC) potentials reduce finite-size errors and accelerate thermodynamic-limit convergence in periodic Hartree--Fock (HF) calculations, but their use with Gaussian basis sets is complicated by the evaluation of electron repulsion integrals (ERIs), particularly for nonspherical truncation domains and all-electron calculations. We introduce the smoothed truncated Coulomb (sTC) potential as a systematically improvable approximation to a parent TC potential. A real-space Gaussian convolution smooths the sharp truncation boundary, and a single dimensionless parameter, $η$, controls the width of the smoothing window, which can be tightened to systematically approach the TC reference. The smoothing by sTC enables a dual-space algorithm for evaluating periodic Gaussian-basis ERIs that requires neither a large plane-wave basis nor new molecular integral kernels and is applicable to both pseudopotential and all-electron calculations, including the important Wigner--Seitz-cell truncation boundaries. Benchmarks spanning insulating, semiconducting, layered, metallic, and molecular-crystal systems show that sTC-based HF closely reproduces TC results in pseudopotential calculations and extends TC-quality calculations to all-electron settings. Across these systems, sTC substantially improves thermodynamic-limit convergence relative to the probe-charge Ewald method while remaining practical for all-electron calculations in which direct TC-based calculations are computationally challenging.
