Optimized effective potentials from the random-phase approximation: Accuracy of the quasiparticle approximation

Author(s)
Stefan Riemelmoser, Merzuk Kaltak, Georg Kresse
Abstract

The optimized effective potential (OEP) method presents an unambiguous way to construct the Kohn-Sham potential corresponding to a given diagrammatic approximation for the exchange-correlation functional. The OEP from the random-phase approximation (RPA) has played an important role ever since the conception of the OEP formalism. However, the solution of the OEP equation is computationally fairly expensive and has to be done in a self-consistent way. So far, large scale solid state applications have, therefore, been performed only using the quasiparticle approximation (QPA), neglecting certain dynamical screening effects. We obtain the exact RPA-OEP for 15 semiconductors and insulators by direct solution of the linearized Sham-Schluter equation. We investigate the accuracy of the QPA on Kohn-Sham bandgaps and dielectric constants, and comment on the issue of self-consistency.

Organisation(s)
Computational Materials Physics
External organisation(s)
VASP Software GmbH
Journal
Journal of Chemical Physics
Volume
154
No. of pages
17
ISSN
0021-9606
DOI
https://doi.org/10.1063/5.0045400
Publication date
04-2021
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics, 103006 Chemical physics
Portal url
https://ucris.univie.ac.at/portal/en/publications/optimized-effective-potentials-from-the-randomphase-approximation-accuracy-of-the-quasiparticle-approximation(7f9776df-db57-4485-85f7-7ad2511bf379).html