General Approach for Reducing Continuous Translational Symmetry Errors in Finite Difference Real-Space Calculations.,Journal of Chemical Theory and Computation

当前位置： X-MOL 学术 › J. Chem. Theory Comput. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

General Approach for Reducing Continuous Translational Symmetry Errors in Finite Difference Real-Space Calculations.
Journal of Chemical Theory and Computation ( IF 5.7 ) Pub Date : 2020-05-26 , DOI: 10.1021/acs.jctc.0c00238
Tian Qiu ₁ , Leeor Kronik ₂ , Andrew M Rappe ₁

Affiliation

We provide a new scheme for representing pseudopotentials on a finite real-space grid, designed to significantly reduce the “egg box” (also known as the “egg carton”) effect, i.e., unphysical fluctuations of computed quantities upon real-space translation. Instead of interpolating the electron–ion potential onto the grid, our scheme starts at a reference position and then uses a weighted sum of translation operators to account for the positions of atoms in real space. This results in a nonlocal but banded representation (even for local potentials) which is fully compatible with nonlocal pseudopotential operators. As a demonstration, this scheme is tested in one dimension for three types of potentials: a local pseudopotential, a nonlocal pseudopotential, and a local pseudopotential with self-consistent Hartree and exchange-correlation potentials. This scheme is found to reduce fluctuations of examined quantities by at least three orders of magnitude. The approach requires neither grid adaptation nor pseudopotential modification and can be readily extended to the three-dimensional case.

中文翻译：

减少有限差分实空间计算中的连续平移对称误差的通用方法。

我们提供了一种用于表示有限实空间网格上的伪势的新方案，旨在显着减少“蛋盒”（也称为“蛋箱”）的影响，即例如，在实空间转换时计算量的非物理波动。我们的方案不是将电子离子电势插值到网格上，而是从参考位置开始，然后使用平移算符的加权总和来说明原子在真实空间中的位置。这导致了非局部但有条带的表示（即使对于局部电势也是如此），它与非局部伪电势算子完全兼容。作为演示，此方案在一维中针对三种类型的电势进行了测试：局部伪势，非局部伪势和具有自洽Hartree势和交换相关势的局部伪势。发现该方案将检查量的波动减小了至少三个数量级。

更新日期：2020-07-14

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11