Rojas, Onofre; Corrêa Silva, E.V.; de Souza, S.M.; … - In: Physica A: Statistical Mechanics and its Applications 356 (2005) 2, pp. 575-588
A special class of S=1 spin ladder Hamiltonians, with second-neighbor exchange interactions and with anisotropies in the z-direction, can be mapped onto one-dimensional composite S=2 (tetrahedral S=1) models. We calculate the high temperature expansion of the Helmoltz free energy for the latter...