HEISENBERG-MODEL CLUSTER-EXPANSION FOR HALF-FILLED HUBBARD AND PPP MODELS uri icon

abstract

  • Pariser-Parr-Pople, Hubbard, and Heisenberg models for systems with one electron per site, such as the n-networks of neutral conjugated hydrocarbons, are considered. It is argued that for usual systems the Hubbard model describes reasonably only those states that are also capable of being so described by a Heisenberg model. Such Heisenberg models are given by a cluster expansion, surpassing in accuracy the results of correspondingly low-order degenerate perturbation expansions. 1989 Taylor & Francis Group, LLC.

published proceedings

  • MOLECULAR PHYSICS

author list (cited authors)

  • POSHUSTA, R. D., SCHMALZ, T. G., & KLEIN, D. J.

citation count

  • 25

complete list of authors

  • POSHUSTA, RD||SCHMALZ, TG||KLEIN, DJ

publication date

  • February 1989