Laboratoire de Chimie Théorique, Sorbonne Université and CNRS, F-75005 Paris, France.
Institut Universitaire de France, F-75005 Paris, France.
J Chem Phys. 2023 Jun 21;158(23). doi: 10.1063/5.0156317.
The basis-set correction method based on density-functional theory consists in correcting the energy calculated by a wave-function method with a given basis set by a density functional. This basis-set correction density functional incorporates the short-range electron correlation effects missing in the basis set. This results in accelerated basis convergences of ground-state energies to the complete-basis-set limit. In this work, we extend the basis-set correction method to a linear-response formalism for calculating excited-state energies. We give the general linear-response equations as well as the more specific equations for configuration-interaction wave functions. As a proof of concept, we apply this approach to the calculations of excited-state energies in a one-dimensional two-electron model system with harmonic potential and a Dirac-delta electron-electron interaction. The results obtained with full-configuration-interaction wave functions expanded in a basis of Hermite functions and a local-density-approximation basis-set correction functional show that the present approach does not help in accelerating the basis convergence of excitation energies. However, we show that it significantly accelerates basis convergences of excited-state total energies.
基于密度泛函理论的基组校正方法包括通过密度泛函校正给定基组的波函数方法计算的能量。该基组校正密度泛函包含基组中缺失的短程电子相关效应。这导致基组收敛速度加快，从而达到完全基组极限的基组收敛速度。在这项工作中，我们将基组校正方法扩展到用于计算激发态能量的线性响应形式。我们给出了一般的线性响应方程以及对于组态相互作用波函数的更具体的方程。作为概念验证，我们将该方法应用于具有调和势和狄拉克 δ 电子-电子相互作用的一维双电子模型系统中激发态能量的计算。使用扩展到 Hermite 函数基和局域密度近似基组校正泛函的完全组态相互作用波函数计算得到的结果表明，该方法无助于加快激发能的基组收敛速度。然而，我们表明它显著地加速了激发态总能量的基组收敛速度。
