2026-04-14T02:07:54Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1997492025-12-04T20:48:29Zcom_2072_1057col_2072_478822col_2072_478917

urn:hdl:2445/199749 Variational localized-site cluster expansions. II. Trees and near trees Klein, D.J. García Bach, Ma. de los Ángeles Termodinàmica estadística Teoria de grafs Arbres Statistical thermodynamics Graph theory Trees Cluster expanded wavefunctions involving localized‐site states and only pair excitations between nearest neighbor sites are considered. In the case that the bonds connecting these nearest neighbor sites form a tree graph (without rings), exact matrix element formulas are obtained in terms of the inverse of a modified type of topological matrix associated with this tree graph. The treatment of some near‐tree cases, without any touching rings, is also discussed. 2023-06-23T16:45:59Z 2023-06-23T16:45:59Z 1976 2023-06-23T16:45:59Z info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Reproducció del document publicat a: https://doi.org/10.1063/1.432144 Journal of Chemical Physics, 1976, vol. 64, p. 4873-4877 https://doi.org/10.1063/1.432144 (c) American Institute of Physics (AIP), 1976 info:eu-repo/semantics/openAccess American Institute of Physics (AIP) Articles publicats en revistes (Física de la Matèria Condensada)