Abstract
For pt.I see ibid., vol.8, p.4037 (1975). The method of data analysis developed previously is applied to the analysis of real specific heat data for three rare earth salts, DAG, GdVO4 and GdAlO3, and MnCl2.4H2O. All these compounds order antiferromagnetically at liquid helium temperature. The data are fitted to C/R=B+A(T/TN-1)- alpha for T>TN, and it is found that alpha =0.13+or-0.04 for all four compounds, A approximately=-B=1.2+or-0.5 for the three rare earth salts and A approximately=-B=2.0+or-0.7 for MnCl2.4H2O. This is in surprisingly good agreement with theoretical Ising model predictions of alpha =1/8, A approximately=1.1 and B approximately=-1.24, despite the fact that only DAG and MnCl2.4H2O have Ising-like anisotropy. For all four compounds the Neel temperature was found to lie between 1/2 and 11/2 mK above the specific heat peak.

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