Koopmans' condition for density-functional theory
Abstract
In approximate Kohn-Sham density-functional theory, self-interaction manifests itself as the dependence of the energy of an orbital on its fractional occupation. This unphysical behavior translates into qualitative and quantitative errors that pervade many fundamental aspects of density-functional predictions. Here, we first examine self-interaction in terms of the discrepancy between total and partial electron removal energies, and then highlight the importance of imposing the generalized Koopmans' condition - that identifies orbital energies as opposite total electron removal energies - to resolve this discrepancy. In the process, we derive a correction to approximate functionals that, in the frozen-orbital approximation, eliminates the unphysical occupation dependence of orbital energies up to the third order in the single-particle densities. This non-Koopmans correction brings physical meaning to single-particle energies; when applied to common local or semilocal density functionals it provides results that are in excellent agreement with experimental data - with an accuracy comparable to that of GW many-body perturbation theory - while providing an explicit total energy functional that preserves or improves on the description of established structural properties.
- Authors:
-
- CERMICS, Projet Micmac ENPC-INRIA, Universite Paris-Est, 6-8 avenue Blaise Pascal, 77455 Marne-la-Vallee Cedex 2 (France)
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
- Department of Physics, Institute of Theoretical Physics and Astrophysics, and Fujian Key Laboratory of Semiconductor Materials and Applications, Xiamen University, Xiamen 361005 (China)
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)
- Publication Date:
- OSTI Identifier:
- 21421419
- Resource Type:
- Journal Article
- Journal Name:
- Physical Review. B, Condensed Matter and Materials Physics
- Additional Journal Information:
- Journal Volume: 82; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevB.82.115121; (c) 2010 The American Physical Society; Journal ID: ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ACCURACY; APPROXIMATIONS; CORRECTIONS; DENSITY; DENSITY FUNCTIONAL METHOD; ELECTRONS; FORECASTING; INTERACTIONS; MANY-BODY PROBLEM; PERTURBATION THEORY; CALCULATION METHODS; ELEMENTARY PARTICLES; FERMIONS; LEPTONS; PHYSICAL PROPERTIES; VARIATIONAL METHODS
Citation Formats
Dabo, Ismaila, Ferretti, Andrea, Poilvert, Nicolas, Marzari, Nicola, Li, Yanli, and Cococcioni, Matteo. Koopmans' condition for density-functional theory. United States: N. p., 2010.
Web. doi:10.1103/PHYSREVB.82.115121.
Dabo, Ismaila, Ferretti, Andrea, Poilvert, Nicolas, Marzari, Nicola, Li, Yanli, & Cococcioni, Matteo. Koopmans' condition for density-functional theory. United States. https://doi.org/10.1103/PHYSREVB.82.115121
Dabo, Ismaila, Ferretti, Andrea, Poilvert, Nicolas, Marzari, Nicola, Li, Yanli, and Cococcioni, Matteo. 2010.
"Koopmans' condition for density-functional theory". United States. https://doi.org/10.1103/PHYSREVB.82.115121.
@article{osti_21421419,
title = {Koopmans' condition for density-functional theory},
author = {Dabo, Ismaila and Ferretti, Andrea and Poilvert, Nicolas and Marzari, Nicola and Li, Yanli and Cococcioni, Matteo},
abstractNote = {In approximate Kohn-Sham density-functional theory, self-interaction manifests itself as the dependence of the energy of an orbital on its fractional occupation. This unphysical behavior translates into qualitative and quantitative errors that pervade many fundamental aspects of density-functional predictions. Here, we first examine self-interaction in terms of the discrepancy between total and partial electron removal energies, and then highlight the importance of imposing the generalized Koopmans' condition - that identifies orbital energies as opposite total electron removal energies - to resolve this discrepancy. In the process, we derive a correction to approximate functionals that, in the frozen-orbital approximation, eliminates the unphysical occupation dependence of orbital energies up to the third order in the single-particle densities. This non-Koopmans correction brings physical meaning to single-particle energies; when applied to common local or semilocal density functionals it provides results that are in excellent agreement with experimental data - with an accuracy comparable to that of GW many-body perturbation theory - while providing an explicit total energy functional that preserves or improves on the description of established structural properties.},
doi = {10.1103/PHYSREVB.82.115121},
url = {https://www.osti.gov/biblio/21421419},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
issn = {1098-0121},
number = 11,
volume = 82,
place = {United States},
year = {Wed Sep 15 00:00:00 EDT 2010},
month = {Wed Sep 15 00:00:00 EDT 2010}
}