Local correlation functional for electrons in two dimensions

S. Pittalis, E. Räsänen, and M. A. L. Marques
Phys. Rev. B 78, 195322 – Published 21 November 2008

Abstract

We derive a local approximation for the correlation energy in two-dimensional electronic systems. In the derivation we follow the scheme originally developed by Colle and Salvetti for three dimensions and consider a Gaussian approximation for the pair density. Then, we introduce an ad hoc modification which better accounts for both the long-range correlation and the kinetic-energy contribution to the correlation energy. The resulting functional is local and depends parametrically on the number of electrons in the system. We apply this functional to the homogeneous electron gas and to a set of two-dimensional quantum dots covering a wide range of electron densities and thus various amounts of correlation. In all test cases we find an excellent agreement between our results and the exact correlation energies. Our correlation functional has a form that is simple and straightforward to implement but broadly outperforms the commonly used local-density approximation.

  • Figure
  • Received 2 July 2008

DOI:https://doi.org/10.1103/PhysRevB.78.195322

©2008 American Physical Society

Authors & Affiliations

S. Pittalis1,2,*, E. Räsänen1,2,4,†, and M. A. L. Marques2,3,‡

  • 1Institut für Theoretische Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
  • 2European Theoretical Spectroscopy Facility (ETSF)
  • 3Laboratoire de Physique de la Matière Condensé et Nanostructures, Université Lyon I, CNRS-UMR 5586, Domaine Scientifique de la Doua, F-69622 Villeurbanne Cedex, France
  • 4Nanoscience Center, Department of Physics, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland

  • *pittalis@physik.fu-berlin.de
  • erasanen@jyu.fi
  • marques@tddft.org

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 78, Iss. 19 — 15 November 2008

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×