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Spin-free quantum chemistry. XVI. Spin correlation

✍ Scribed by F. A. Matsen; T. L. Welsher

Publisher
John Wiley and Sons
Year
1975
Tongue
English
Weight
700 KB
Volume
9
Category
Article
ISSN
0020-7608

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✦ Synopsis

Abstract

We discuss the calculation of quasielastic critical neutron scattering for systems defined by a spin‐free Hamiltonian. The system dependent property which determines the critical scattering is the thermal average of a spin‐free operator called the general unpaired electron correlation operator. For localized models, we obtain the scattering as the Fourier transform of an unpaired site correlation function. The algebraic relationship between this correlation function and the usual spin correlation function is discussed as are its relationships to thermodynamic properties. Correlations in the infinite interaction range model, linear spin wave model, and infinite chain Heisenberg model are given. In the last case, an estimate of the low temperature correlation length is made.

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