On Augmented Kohn-Sham Potential for Energy as a Simple Sum of Orbital Energies

TL;DR

This paper explores a simplified approach to calculating ground-state energy in density functional theory by summing augmented Kohn-Sham orbital energies, analyzing the properties of the associated effective potential.

Contribution

It introduces eigenvalue and virial constraints for approximating the augmented Kohn-Sham potential, advancing the understanding of energy calculations in DFT.

Findings

Ground-state energy can be obtained as a sum of augmented orbital energies.

The effective potential has appealing features that can be approximated.

Eigenvalue and virial constraints are derived for potential approximation.

Abstract

It has recently been observed [Phys. Rev. Lett. 113, 113002 (2014)] that the ground-state energy may be obtained directly as a simple sum of augmented Kohn-Sham orbital energies, where it was ascertained that the corresponding one-body shifted Kohn-Sham effective potential has appealing features. With this in mind, eigenvalue and virial constraints are deduced for approximating this potential.