Selfinteraction in Green'sfunction theory of the hydrogen atom
Abstract
Atomic hydrogen provides a unique test case for computational electronic structure methods, since its electronic excitation energies are known analytically. With only one electron, hydrogen contains no electronic correlation and is therefore particularly susceptible to spurious selfinteraction errors introduced by certain computational methods. In this paper we focus on manybody perturbation theory (MBPT) in Hedin's GW approximation. While the HartreeFock and the exact MBPT selfenergy are free of selfinteraction, the correlation part of the GW selfenergy does not have this property. Here we use atomic hydrogen as a benchmark system for GW and show that the selfinteraction part of the GW selfenergy, while nonzero, is small. The effect of calculating the GW selfenergy from exact wave functions and eigenvalues, as distinct from those from the localdensity approximation, is also illuminating.
 Authors:
 Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)
 Department of Physics, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkovicova 3, 841 04 Bratislava (Slovakia)
 FritzHaberInstitut der MaxPlanckGesellschaft, Faradayweg 46, 14195 Berlin (Germany)
 Publication Date:
 OSTI Identifier:
 20982302
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032505; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; BENCHMARKS; COMPUTER CALCULATIONS; CORRELATIONS; DENSITY; DENSITY FUNCTIONAL METHOD; EIGENFUNCTIONS; EIGENVALUES; ELECTRONIC STRUCTURE; ELECTRONS; EXCITATION; GREEN FUNCTION; HARTREEFOCK METHOD; HYDROGEN; INTERACTIONS; MANYBODY PROBLEM; PERTURBATION THEORY; SELFENERGY; WAVE FUNCTIONS
Citation Formats
Nelson, W., Bokes, P., Rinke, Patrick, and Godby, R. W. Selfinteraction in Green'sfunction theory of the hydrogen atom. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.032505.
Nelson, W., Bokes, P., Rinke, Patrick, & Godby, R. W. Selfinteraction in Green'sfunction theory of the hydrogen atom. United States. doi:10.1103/PHYSREVA.75.032505.
Nelson, W., Bokes, P., Rinke, Patrick, and Godby, R. W. Thu .
"Selfinteraction in Green'sfunction theory of the hydrogen atom". United States.
doi:10.1103/PHYSREVA.75.032505.
@article{osti_20982302,
title = {Selfinteraction in Green'sfunction theory of the hydrogen atom},
author = {Nelson, W. and Bokes, P. and Rinke, Patrick and Godby, R. W.},
abstractNote = {Atomic hydrogen provides a unique test case for computational electronic structure methods, since its electronic excitation energies are known analytically. With only one electron, hydrogen contains no electronic correlation and is therefore particularly susceptible to spurious selfinteraction errors introduced by certain computational methods. In this paper we focus on manybody perturbation theory (MBPT) in Hedin's GW approximation. While the HartreeFock and the exact MBPT selfenergy are free of selfinteraction, the correlation part of the GW selfenergy does not have this property. Here we use atomic hydrogen as a benchmark system for GW and show that the selfinteraction part of the GW selfenergy, while nonzero, is small. The effect of calculating the GW selfenergy from exact wave functions and eigenvalues, as distinct from those from the localdensity approximation, is also illuminating.},
doi = {10.1103/PHYSREVA.75.032505},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}

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