General-order many-body greens function method

So Hirata, Matthew R. Hermes, Jack Simons, J. V. Ortiz

Research output: Contribution to journalArticle

Abstract

Electron binding energies are evaluated as differences in total energy between the N- and (N ± 1)-electron systems calculated by the nth-order Møller-Plesset perturbation (MPn) theory using the same set of orbitals. The MPn energies up to n = 30 are, in turn, obtained by the determinant-based method of Knowles et al. (Chem. Phys. Lett. 1985, 113, 8-12). The zeroth- through third-order electron binding energies thus determined agree with those obtained by solving the Dyson equation in the diagonal and frequency-independent approximations of the self-energy. However, as n → ∞, they converge at the exact basis-set solutions from the Dyson equation with the exact self-energy, which is nondiagonal and frequency-dependent. This suggests that the MPn energy differences define an alternative diagrammatic expansion of Koopmans-like electron binding energies, which takes into account the perturbation corrections from the off-diagonal elements and frequency dependence of the irreducible self-energy. Our analysis shows that these corrections are included as semireducible and linked-disconnected diagrams, respectively, which are also found in a perturbation expansion of the electron binding energies of the equation-of-motion coupled-cluster methods. The rate of convergence of the electron binding energies with respect to n and its acceleration by Padé approximants are also discussed.

Original languageEnglish (US)
Pages (from-to)1595-1606
Number of pages12
JournalJournal of Chemical Theory and Computation
Volume11
Issue number4
DOIs
StatePublished - Apr 14 2015

ASJC Scopus subject areas

  • Computer Science Applications
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'General-order many-body greens function method'. Together they form a unique fingerprint.

  • Cite this