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Title: Generalized Pauli constraints in reduced density matrix functional theory

Abstract

Functionals of the one-body reduced density matrix (1-RDM) are routinely minimized under Coleman’s ensemble N-representability conditions. Recently, the topic of pure-state N-representability 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 pure-state conditions on the results of reduced density-matrix functional theory calculations. In particular, we examine whether the standard minimization of typical 1-RDM functionals under the ensemble N-representability conditions violates the pure-state conditions for prototype 3-electron systems. We also enforce the pure-state 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:
;  [1];  [2];  [3];  [4]
  1. Peter-Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich, D-52425 Jülich (Germany)
  2. Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, Vass. Constantinou 48, GR-11635 Athens (Greece)
  3. (Saale) (Germany)
  4. Institut für Physik Martin-Luther-Universität Halle-Wittenberg, D-06120 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., Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 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., Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 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., Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 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 Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle and Marques, Miguel A. L.},
abstractNote = {Functionals of the one-body reduced density matrix (1-RDM) are routinely minimized under Coleman’s ensemble N-representability conditions. Recently, the topic of pure-state N-representability 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 pure-state conditions on the results of reduced density-matrix functional theory calculations. In particular, we examine whether the standard minimization of typical 1-RDM functionals under the ensemble N-representability conditions violates the pure-state conditions for prototype 3-electron systems. We also enforce the pure-state 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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