Title: Construction of exchange-correlation functionals through interpolation between the non-interacting and the strong-correlation limit

Drawing on the adiabatic connection of density functional theory, exchange-correlation functionals of Kohn-Sham density functional theory are constructed which interpolate between the extreme limits of the electron-electron interaction strength. The first limit is the non-interacting one, where there is only exchange. The second limit is the strong correlated one, characterized as the minimum of the electron-electron repulsion energy. The exchange-correlation energy in the strong-correlation limit is approximated through a model for the exchange-correlation hole that is referred to as nonlocal-radius model [L. O. Wagner and P. Gori-Giorgi, Phys. Rev. A 90, 052512 (2014)]. Using the non-interacting and strong-correlated extremes, various interpolation schemes are presented that yield new approximations to the adiabatic connection and thus to the exchange-correlation energy. Some of them rely on empiricism while others do not. Several of the proposed approximations yield the exact exchange-correlation energy for one-electron systems where local and semi-local approximations often fail badly. Other proposed approximations generalize existing global hybrids by using a fraction of the exchange-correlation energy in the strong-correlation limit to replace an equal fraction of the semi-local approximation to the exchange-correlation energy in the strong-correlation limit. The performance of the proposed approximations is evaluated for molecular atomization energies, total atomic energies,more » and ionization potentials.« less

Département de Chimie, Université de Montréal, C.P. 6128, Succursale A, Montréal, Québec H3C 3J7 (Canada)

Department of Chemistry, Technische Universität Berlin, Strasse des 17 Juni, Berlin (Germany)

Publication Date:

OSTI Identifier:

22489627

Resource Type:

Journal Article

Resource Relation:

Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 97 MATHEMATICAL METHODS AND COMPUTING; APPROXIMATIONS; ATOMIZATION; DENSITY FUNCTIONAL METHOD; ELECTRON CORRELATION; ELECTRON-ELECTRON COLLISIONS; ELECTRON-ELECTRON INTERACTIONS; ELECTRONS; HYBRIDIZATION; INTERPOLATION; NUCLEAR ENERGY