Eliminating Delocalization Error in Density Functional Theory with Linear Response Localized Orbital Scaling Correction

Delocalization error is a persistent challenge in Kohn-Sham density functional theory (KS-DFT) calculations that use density functional approximations (DFAs), leading to inaccuracies in ionization energies, electron affinities, band structures, and charge distributions. The recently developed linear response localized orbital scaling correction (lrLOSC) effectively addresses these issues by incorporating both screening effects and orbital localization. In this work, we extend lrLOSC to a wider range of molecular systems, focusing on corrections to valence orbital energies and tota energy. Our results demonstrate that the inclusion of orbital relaxation effect enhances accuracy across varying molecular sizes, while orbital localization yields modest improvements for small molecules, it is essential for achieving high accuracy in larger linear and nonlinear molecules. We also introduce an efficient implementation of lrLOSC that provides reliable orbital and total energy corrections with a computational cost comparable to standard KS-DFT. These findings underscore lrLOSC's capability to provide accurate energy corrections, outperforming existing methods such as localized orbital scaling correction without screening and global scaling correction. This advancement has significant implications for improving the reliability of chemical simulations across a wide range of systems.