Double, Rydberg and charge transfer excitations from pairing matrix fluctuation and particle-particle random phase approximation.

Published

Journal Article

Double, Rydberg, and charge transfer (CT) excitations have been great challenges for time-dependent density functional theory (TDDFT). Starting from an (N ± 2)-electron single-determinant reference, we investigate excitations for the N-electron system through the pairing matrix fluctuation, which contains information on two-electron addition/removal processes. We adopt the particle-particle random phase approximation (pp-RPA) and the particle-particle Tamm-Dancoff approximation (pp-TDA) to approximate the pairing matrix fluctuation and then determine excitation energies by the differences of two-electron addition/removal energies. This approach captures all types of interesting excitations: single and double excitations are described accurately, Rydberg excitations are in good agreement with experimental data and CT excitations display correct 1/R dependence. Furthermore, the pp-RPA and the pp-TDA have a computational cost similar to TDDFT and consequently are promising for practical calculations.

Full Text

Duke Authors

Cited Authors

  • Yang, Y; van Aggelen, H; Yang, W

Published Date

  • December 2013

Published In

Volume / Issue

  • 139 / 22

Start / End Page

  • 224105 -

PubMed ID

  • 24329054

Pubmed Central ID

  • 24329054

Electronic International Standard Serial Number (EISSN)

  • 1089-7690

International Standard Serial Number (ISSN)

  • 0021-9606

Digital Object Identifier (DOI)

  • 10.1063/1.4834875

Language

  • eng