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The importance of middle-range Hartree-Fock-type exchange for hybrid density functionals.
- Source :
-
Journal of Chemical Physics . Dec2007, Vol. 127 Issue 22, p221103. 4p. 1 Chart, 2 Graphs. - Publication Year :
- 2007
-
Abstract
- Hybrid functionals are responsible for much of the utility of modern Kohn-Sham density functional theory. When rigorously applied to solid-state metallic and small band gap systems, however, the slow decay of their nonlocal Hartree-Fock-type exchange makes hybrids computationally challenging and introduces unphysical effects. This can be remedied by using a range-separated hybrid which only keeps short-range nonlocal exchange, as in the functional of Heyd et al. [J. Chem. Phys. 118, 8207 (2003)]. On the other hand, many molecular properties require full long-range nonlocal exchange, which can also be included by means of a range-separated hybrid such as the recently introduced LC-ωPBE functional [O. A. Vydrov and G. E. Scuseria, J. Chem. Phys. 125, 234109 (2006)]. In this paper, we show that a three-range hybrid which mainly includes middle-range Hartree-Fock-type exchange and neglects long- and short-range Hartree-Fock-type exchange yields excellent accuracy for thermochemistry, barrier heights, and band gaps, emphasizing that the middle-range part of the 1/r potential seems crucial to accurately model these properties. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 00219606
- Volume :
- 127
- Issue :
- 22
- Database :
- Academic Search Index
- Journal :
- Journal of Chemical Physics
- Publication Type :
- Academic Journal
- Accession number :
- 28001406
- Full Text :
- https://doi.org/10.1063/1.2822021