Variational energy functionals of the Green function and of the density tested on molecules
Abstract
We have calculated total energies of atoms and diatomic molecules from the LuttingerWard functional, using selfenergy approximations to second order as well as the GW approximation. In order to assess the variational quality of this functional, we have also solved the Dyson equation selfconsistently. The LuttingerWard functional is compared to the variational functional due to Klein, and we demonstrate that the variational property of the latter functional is inferior to that of the LuttingerWard functional. We also show how to obtain variational density functionals from the functionals of the Green function. These orbital functional schemes are important for systems where densityfunctional theory using local functionals of the density necessarily fails. We derive an optimized effective potential (OEP) scheme that is based on the LuttingerWard functional and, unlike the conventional OEP schemes, produces energies in good agreement with the values obtained from the selfconsistent Green function. Our calculations show that, when applied to molecules, the LuttingerWard functional is more sensitive to the quality of the input Green function than when applied to atoms, but the energies are remarkably close to the selfconsistent values when the HartreeFock Green function is used as input. This LuttingerWard functional is therefore a simple and efficientmore »
 Authors:
 Theoretical Chemistry, Materials Science Centre, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)
 (Sweden)
 Publication Date:
 OSTI Identifier:
 20786701
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.012511; (c) 2006 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; DENSITY; DENSITY FUNCTIONAL METHOD; ENERGY DENSITY; GREEN FUNCTION; HARTREEFOCK METHOD; MOLECULES; POTENTIALS; SELFENERGY
Citation Formats
Dahlen, Nils Erik, Leeuwen, Robert van, Barth, Ulf von, and Department of Physics, Lund University, Soelvegatan 14 A, SE22362 Lund. Variational energy functionals of the Green function and of the density tested on molecules. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVA.73.0.
Dahlen, Nils Erik, Leeuwen, Robert van, Barth, Ulf von, & Department of Physics, Lund University, Soelvegatan 14 A, SE22362 Lund. Variational energy functionals of the Green function and of the density tested on molecules. United States. doi:10.1103/PHYSREVA.73.0.
Dahlen, Nils Erik, Leeuwen, Robert van, Barth, Ulf von, and Department of Physics, Lund University, Soelvegatan 14 A, SE22362 Lund. Sun .
"Variational energy functionals of the Green function and of the density tested on molecules". United States.
doi:10.1103/PHYSREVA.73.0.
@article{osti_20786701,
title = {Variational energy functionals of the Green function and of the density tested on molecules},
author = {Dahlen, Nils Erik and Leeuwen, Robert van and Barth, Ulf von and Department of Physics, Lund University, Soelvegatan 14 A, SE22362 Lund},
abstractNote = {We have calculated total energies of atoms and diatomic molecules from the LuttingerWard functional, using selfenergy approximations to second order as well as the GW approximation. In order to assess the variational quality of this functional, we have also solved the Dyson equation selfconsistently. The LuttingerWard functional is compared to the variational functional due to Klein, and we demonstrate that the variational property of the latter functional is inferior to that of the LuttingerWard functional. We also show how to obtain variational density functionals from the functionals of the Green function. These orbital functional schemes are important for systems where densityfunctional theory using local functionals of the density necessarily fails. We derive an optimized effective potential (OEP) scheme that is based on the LuttingerWard functional and, unlike the conventional OEP schemes, produces energies in good agreement with the values obtained from the selfconsistent Green function. Our calculations show that, when applied to molecules, the LuttingerWard functional is more sensitive to the quality of the input Green function than when applied to atoms, but the energies are remarkably close to the selfconsistent values when the HartreeFock Green function is used as input. This LuttingerWard functional is therefore a simple and efficient method for studying the merits of various selfenergy approximations while avoiding the computationally demanding task of solving the Dyson equation selfconsistently.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}

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