Damping of perturbation corrections in quasidegenerate situations

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Shifting the pole of the energy denominators from the real axis to the imaginary results in a damping of the equation in degenerate cases. The term-by-term absolute value of the expression provides a simple and useful formula to treat quasidegenerate problems. The power of the new expression is illustrated on several examples calculating the correlation energy of some molecules. The Møller-Plesset results are scarcely affected by the proposed modification in normal cases but significant improvement is observed in quasidegenerate situations. The proposed formula is size consistent and its evaluation does not need extra computational effort.

Original languageEnglish
Pages (from-to)3320-3324
Number of pages5
JournalThe Journal of Chemical Physics
Volume104
Issue number9
Publication statusPublished - 1996

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Poles
Damping
damping
perturbation
Molecules
poles
energy
evaluation
molecules

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Cite this

Damping of perturbation corrections in quasidegenerate situations. / Surján, P.; Szabados, A.

In: The Journal of Chemical Physics, Vol. 104, No. 9, 1996, p. 3320-3324.

Research output: Contribution to journalArticle

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