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International Journal of Quantum Chemistry

Variational localized-site cluster expansions. XI. Coherent state derivation of effective heisenberg hamiltonians

Douglas J. Klein, W. A. Seitz, M. A. García‐Bach, J. M. Picone, David C. Foyt

Published Jul 9, 2009• 1 citation
Publisher

Abstract

A variational derivation of Heisenberg or valence-bond models from a Hubbard (or Pariser-Parr-Pople) Hamiltonian is described. Calculations within a low-order approximation are carried out for linear-chain and graphite lattices. The results seem to be quite accurate with little computational effort when compared with other approaches.
DOI
10.1002/qua.560240860

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