Quasidegenerate perturbation theory with multiconfigurational self-consistent-field reference functions

Research output: Contribution to journalArticle

781 Citations (Scopus)

Abstract

A quasidegenerate perturbation theory based on multiconfigurational self-consistent-field (MCSCF) reference functions is derived. The perturbation theory derived here is for multistate, where several MGSCF functions obtained by the state-averaged MCSCF method are used as the reference and an effective Hamiltonian is constructed by perturbation calculation. The energies of states interested in are obtained simultaneously by diagonalization of the effective Hamiltonian. An explicit formula of the effective Hamiltonian through second order is derived as well as general formalism, and is applied to calculate potential curves of the system H2, Be-H2, CO, NO, BN, and LiF. The results agree well with those of full configuration interaction or multireference single and double excitation configuration interaction methods for both the ground and the excited states.

Original languageEnglish
Pages (from-to)7983-7992
Number of pages10
JournalThe Journal of Chemical Physics
Volume99
Issue number10
DOIs
Publication statusPublished - Jan 1 1993
Externally publishedYes

Fingerprint

Hamiltonians
configuration interaction
self consistent fields
perturbation theory
excitation
Carbon Monoxide
formalism
Excited states
perturbation
curves
energy

All Science Journal Classification (ASJC) codes

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

Cite this

Quasidegenerate perturbation theory with multiconfigurational self-consistent-field reference functions. / Nakano, Haruyuki.

In: The Journal of Chemical Physics, Vol. 99, No. 10, 01.01.1993, p. 7983-7992.

Research output: Contribution to journalArticle

@article{9a50da3222984ed0a00032076e7d7768,
title = "Quasidegenerate perturbation theory with multiconfigurational self-consistent-field reference functions",
abstract = "A quasidegenerate perturbation theory based on multiconfigurational self-consistent-field (MCSCF) reference functions is derived. The perturbation theory derived here is for multistate, where several MGSCF functions obtained by the state-averaged MCSCF method are used as the reference and an effective Hamiltonian is constructed by perturbation calculation. The energies of states interested in are obtained simultaneously by diagonalization of the effective Hamiltonian. An explicit formula of the effective Hamiltonian through second order is derived as well as general formalism, and is applied to calculate potential curves of the system H2, Be-H2, CO, NO, BN, and LiF. The results agree well with those of full configuration interaction or multireference single and double excitation configuration interaction methods for both the ground and the excited states.",
author = "Haruyuki Nakano",
year = "1993",
month = "1",
day = "1",
doi = "10.1063/1.465674",
language = "English",
volume = "99",
pages = "7983--7992",
journal = "Journal of Chemical Physics",
issn = "0021-9606",
publisher = "American Institute of Physics Publising LLC",
number = "10",

}

TY - JOUR

T1 - Quasidegenerate perturbation theory with multiconfigurational self-consistent-field reference functions

AU - Nakano, Haruyuki

PY - 1993/1/1

Y1 - 1993/1/1

N2 - A quasidegenerate perturbation theory based on multiconfigurational self-consistent-field (MCSCF) reference functions is derived. The perturbation theory derived here is for multistate, where several MGSCF functions obtained by the state-averaged MCSCF method are used as the reference and an effective Hamiltonian is constructed by perturbation calculation. The energies of states interested in are obtained simultaneously by diagonalization of the effective Hamiltonian. An explicit formula of the effective Hamiltonian through second order is derived as well as general formalism, and is applied to calculate potential curves of the system H2, Be-H2, CO, NO, BN, and LiF. The results agree well with those of full configuration interaction or multireference single and double excitation configuration interaction methods for both the ground and the excited states.

AB - A quasidegenerate perturbation theory based on multiconfigurational self-consistent-field (MCSCF) reference functions is derived. The perturbation theory derived here is for multistate, where several MGSCF functions obtained by the state-averaged MCSCF method are used as the reference and an effective Hamiltonian is constructed by perturbation calculation. The energies of states interested in are obtained simultaneously by diagonalization of the effective Hamiltonian. An explicit formula of the effective Hamiltonian through second order is derived as well as general formalism, and is applied to calculate potential curves of the system H2, Be-H2, CO, NO, BN, and LiF. The results agree well with those of full configuration interaction or multireference single and double excitation configuration interaction methods for both the ground and the excited states.

UR - http://www.scopus.com/inward/record.url?scp=33745044263&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33745044263&partnerID=8YFLogxK

U2 - 10.1063/1.465674

DO - 10.1063/1.465674

M3 - Article

AN - SCOPUS:33745044263

VL - 99

SP - 7983

EP - 7992

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 10

ER -