Ensemble density variational methods with selfand ghost-interaction-corrected functionals
| dc.contributor.author | Pastorczak, Ewa | |
| dc.contributor.author | Pernal, Katarzyna | |
| dc.date.accessioned | 2016-02-03T08:35:52Z | |
| dc.date.available | 2016-02-03T08:35:52Z | |
| dc.date.issued | 2014 | |
| dc.description.abstract | Ensemble density functional theory (DFT) offers a way of predicting excited-states energies of atomic and molecular systems without referring to a density response function. Despite a significant theoretical work, practical applications of the proposed approximations have been scarce and they do not allow for a fair judgement of the potential usefulness of ensemble DFT with available functionals. In the paper, we investigate two forms of ensemble density functionals formulated within ensemble DFT framework: the Gross, Oliveira, and Kohn (GOK) functional proposed by Gross et al. [Phys. Rev. A37, 2809 (1988)] alongside the orbital-dependent eDFT form of the functional introduced by Nagy [J. Phys. B34, 2363 (2001)] (the acronym eDFT proposed in analogy to eHF – ensemble Hartree-Fock method). Local and semi-local ground-state density functionals are employed in both approaches. Approximate ensemble density functionals contain not only spurious self-interaction but also the so-called ghost-interaction which has no counterpart in the ground-state DFT. We propose how to correct the GOK functional for both kinds of interactions in approximations that go beyond the exact-exchange functional. Numerical applications lead to a conclusion that functionals free of the ghost-interaction by construction, i.e., eDFT, yield much more reliable results than approximate self- and ghost-interaction-corrected GOK functional. Additionally, local density functional corrected for self-interaction employed in the eDFT framework yields excitations energies of the accuracy comparable to that of the uncorrected semi-local eDFT functional. | en_EN |
| dc.identifier.citation | The Journal of Chemical Physics, Vol. 140, Issue 18, pages 18A514 2 - 18A514 7 | |
| dc.identifier.uri | http://hdl.handle.net/11652/1062 | |
| dc.identifier.uri | http://scitation.aip.org/content/aip/journal/jcp/140/18/10.1063/1.4866998 | |
| dc.language.iso | en | en_EN |
| dc.publisher | American Institute of Physics | en_EN |
| dc.relation.ispartofseries | The Journal of Chemical Physics, Vol. 140, Issue 18, 2014 | en_EN |
| dc.title | Ensemble density variational methods with selfand ghost-interaction-corrected functionals | en_EN |
| dc.type | Artykuł | pl_PL |
| dc.type | Article | en_EN |