The LDA-1/2 method applied to atoms and molecules

Ronaldo Rodrigues Pela; Andris Gulans; Claudia Draxl

doi:10.1021/acs.jctc.8b00518

paper

The LDA-1/2 method applied to atoms and molecules

arXiv:1805.09705 · doi:10.1021/acs.jctc.8b00518

Abstract

The LDA-1/2 method has proven to be a viable approach for calculating band gaps of semiconductors. To address its accuracy for finite systems, we apply LDA-1/2 to atoms and the molecules of the $G W 100$ test set. The obtained energies of the highest-occupied molecular orbitals are validated against CCSD(T) data and the $G_{0} W_{0}$ approach of many-body perturbation theory. The accuracy of LDA-1/2 and $G_{0} W_{0}$ is found to be the same, where the latter is computationally much more involved. To get insight into the benefits and limitations of the LDA-1/2 method, we analyze the impact of each assumption made in deriving the methodology.