Croatica Chemica Acta, Vol. 61 No. 3, 1988.
Original scientific paper
The Multidimensional Pseudo Spin Model and its Application to Phase Transitions in Layered Perovskites
M. Couzi
; Laboratoire de Spectroscopie Moleculaire et Cristaline (UA 124), Universite de Bordeaux I - 33405 Talence, France
Ph. Negrier
; Laboratoire de Cristalographie et Physique Cristaline (UA 144), Universite de Bordeaux I - 33405 Talence, France
H. Poulet
; Departement de Recherches Physiques (UA 71) - Universite Pierre et Marie Curie, 4, place Jussieu - 75005 Paris, France
R. M. Pick
; Departement de Recherches Physiques (UA 71) - Universite Pierre et Marie Curie, 4, place Jussieu - 75005 Paris, France
Abstract
Pseudo spins with dimensionality larger than two may be used to describe disordered molecular, or ionomolecular, crystals in which the molecules have several equivalent orientations. We show that such models predict complex ordering schemes for these crystals, we describe the various problems related to the construction of these schemes and apply this technique in detail to the case of NH3(CH2)sNH3CdC1an4d briefly to other similar layered perovskites.
Keywords
Hrčak ID:
175962
URI
Publication date:
30.11.1988.
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