Variational localized-site cluster expansions
- 1 March 1976
- journal article
- research article
- Published by Taylor & Francis in Molecular Physics
- Vol. 31 (3), 811-823
- https://doi.org/10.1080/00268977600100621
Abstract
The simplest localized-site cluster expansion for a system of doublet sites described within the context of a valence bond or Heisenberg model is considered. Exact matrix element formulae are obtained for a variety of systems, including some with fused rings. Numerical results for the linear chain case suggest that this simple ansatz improves over the common resonance theory presumption of Kekulé structures only.Keywords
This publication has 12 references indexed in Scilit:
- Computations on Heisenberg Spin ModelsInternational Journal of Quantum Chemistry, 1973
- Reduced Density Matrices for Valence Bond Wavefunctions. III. Density Matrices for the 4×4 Square Planar NetThe Journal of Chemical Physics, 1972
- Stability of Antiferromagnetism against Pairwise BondingPhysical Review B, 1969
- Linear Antiferromagnetic ChainPhysical Review B, 1959
- Quantum Theory of Many-Particle Systems. I. Physical Interpretations by Means of Density Matrices, Natural Spin-Orbitals, and Convergence Problems in the Method of Configurational InteractionPhysical Review B, 1955
- Das Kompositions‐Prinzip: Eine anschauliche Methode zur elektronen‐theoretischen Behandlung nicht oder niedrig symmetrischer Molekeln im Rahmen der MO‐TheorieHelvetica Chimica Acta, 1953
- Note on Orthogonal Atomic OrbitalsThe Journal of Chemical Physics, 1951
- On the Non-Orthogonality Problem Connected with the Use of Atomic Wave Functions in the Theory of Molecules and CrystalsThe Journal of Chemical Physics, 1950
- Some Studies in Molecular Orbital Theory I. Resonance Structures and Molecular Orbitals in Unsaturated HydrocarbonsThe Journal of Chemical Physics, 1950
- The electronic structure of some polyenes and aromatic molecules III—Bonds of fractional order by the pair methodProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1937