Generalized Pauli constraints in reduced density matrix functional theory
Abstract
Functionals of the onebody reduced density matrix (1RDM) are routinely minimized under Coleman’s ensemble Nrepresentability conditions. Recently, the topic of purestate Nrepresentability conditions, also known as generalized Pauli constraints, received increased attention following the discovery of a systematic way to derive them for any number of electrons and any finite dimensionality of the Hilbert space. The target of this work is to assess the potential impact of the enforcement of the purestate conditions on the results of reduced densitymatrix functional theory calculations. In particular, we examine whether the standard minimization of typical 1RDM functionals under the ensemble Nrepresentability conditions violates the purestate conditions for prototype 3electron systems. We also enforce the purestate conditions, in addition to the ensemble ones, for the same systems and functionals and compare the correlation energies and optimal occupation numbers with those obtained by the enforcement of the ensemble conditions alone.
 Authors:
 PeterGrünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich, D52425 Jülich (Germany)
 Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, Vass. Constantinou 48, GR11635 Athens (Greece)
 (Saale) (Germany)
 Institut für Physik MartinLutherUniversität HalleWittenberg, D06120 Halle (Saale) (Germany)
 Publication Date:
 OSTI Identifier:
 22415659
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 15; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPARATIVE EVALUATIONS; DENSITY MATRIX; ELECTRON CORRELATION; ELECTRONS; FUNCTIONALS; HILBERT SPACE; LIMITING VALUES; MINIMIZATION; PAULI PRINCIPLE; POTENTIALS; PURE STATES
Citation Formats
Theophilou, Iris, Helbig, Nicole, Lathiotakis, Nektarios N., MaxPlanckInstitut für Mikrostrukturphysik, Weinberg 2, D06120 Halle, and Marques, Miguel A. L.. Generalized Pauli constraints in reduced density matrix functional theory. United States: N. p., 2015.
Web. doi:10.1063/1.4918346.
Theophilou, Iris, Helbig, Nicole, Lathiotakis, Nektarios N., MaxPlanckInstitut für Mikrostrukturphysik, Weinberg 2, D06120 Halle, & Marques, Miguel A. L.. Generalized Pauli constraints in reduced density matrix functional theory. United States. doi:10.1063/1.4918346.
Theophilou, Iris, Helbig, Nicole, Lathiotakis, Nektarios N., MaxPlanckInstitut für Mikrostrukturphysik, Weinberg 2, D06120 Halle, and Marques, Miguel A. L.. 2015.
"Generalized Pauli constraints in reduced density matrix functional theory". United States.
doi:10.1063/1.4918346.
@article{osti_22415659,
title = {Generalized Pauli constraints in reduced density matrix functional theory},
author = {Theophilou, Iris and Helbig, Nicole and Lathiotakis, Nektarios N. and MaxPlanckInstitut für Mikrostrukturphysik, Weinberg 2, D06120 Halle and Marques, Miguel A. L.},
abstractNote = {Functionals of the onebody reduced density matrix (1RDM) are routinely minimized under Coleman’s ensemble Nrepresentability conditions. Recently, the topic of purestate Nrepresentability conditions, also known as generalized Pauli constraints, received increased attention following the discovery of a systematic way to derive them for any number of electrons and any finite dimensionality of the Hilbert space. The target of this work is to assess the potential impact of the enforcement of the purestate conditions on the results of reduced densitymatrix functional theory calculations. In particular, we examine whether the standard minimization of typical 1RDM functionals under the ensemble Nrepresentability conditions violates the purestate conditions for prototype 3electron systems. We also enforce the purestate conditions, in addition to the ensemble ones, for the same systems and functionals and compare the correlation energies and optimal occupation numbers with those obtained by the enforcement of the ensemble conditions alone.},
doi = {10.1063/1.4918346},
journal = {Journal of Chemical Physics},
number = 15,
volume = 142,
place = {United States},
year = 2015,
month = 4
}

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