Ghost- and self-interaction-free ensemble calculations with local exchange–correlationpotential for atoms

Abstract

Though the exact ensemble energy functional is free from self-interaction andghost-interaction (i.e. self-interaction between the elements of the ensemble),approximations generally suffer from both self- and ghost-interactions. Recently, aghost-interaction-free ensemble Kohn–Sham potential has been proposed. Combining thisnewly proposed method with the self-interaction-free Perdew–Zunger approximation, now aghost- and self-interaction-corrected (GSIC) ensemble Kohn–Sham potential ispresented. Total ensemble energies and excitation energies are obtained withGSIC local Vosko–Wilk–Nusair exchange–correlation potential for some lightatoms.