Generalized Hartree-Fock natural-orbital configuration-interaction (GHF NO CI) approach to unstable molecules: trimethylene

Kizashi Yamaguchi, Koji Ohta, Satoshi Yabushita, Takayuki Fueno

Research output: Contribution to journalArticle

53 Citations (Scopus)


A configuration interaction (CI) method by use of natural orbitals (NO) derived from the generalized Hartree-Fock (GHF) solutions is proposed and applied to trimethylene as an example. It is found that the GHF NO CI method is equivalent to the traditional restricted HF (RHF) CI approach in the domain of weak correlation, and is similar to the generalized VB (GVB) CI method in the strong-correlation region. The GHF NO CI method thus seems to be promising for the study of the electronic structure of unstable molecules which are characterized by orbital and spin degeneracies.

Original languageEnglish
Pages (from-to)555-559
Number of pages5
JournalChemical Physics Letters
Issue number3
Publication statusPublished - 1977 Aug 1


ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Cite this