Excitation energies from particle-particle random phase approximation with accurate optimized effective potentials.

Published

Journal Article

The optimized effective potential (OEP) that gives accurate Kohn-Sham (KS) orbitals and orbital energies can be obtained from a given reference electron density. These OEP-KS orbitals and orbital energies are used here for calculating electronic excited states with the particle-particle random phase approximation (pp-RPA). Our calculations allow the examination of pp-RPA excitation energies with the exact KS density functional theory (DFT). Various input densities are investigated. Specifically, the excitation energies using the OEP with the electron densities from the coupled-cluster singles and doubles method display the lowest mean absolute error from the reference data for the low-lying excited states. This study probes into the theoretical limit of the pp-RPA excitation energies with the exact KS-DFT orbitals and orbital energies. We believe that higher-order correlation contributions beyond the pp-RPA bare Coulomb kernel are needed in order to achieve even higher accuracy in excitation energy calculations.

Full Text

Duke Authors

Cited Authors

  • Jin, Y; Yang, Y; Zhang, D; Peng, D; Yang, W

Published Date

  • October 2017

Published In

Volume / Issue

  • 147 / 13

Start / End Page

  • 134105 -

PubMed ID

  • 28987104

Pubmed Central ID

  • 28987104

Electronic International Standard Serial Number (EISSN)

  • 1089-7690

International Standard Serial Number (ISSN)

  • 0021-9606

Digital Object Identifier (DOI)

  • 10.1063/1.4994827

Language

  • eng