Paramagnetism above the Curie Point

Substitution of equation 100 for the Weiss field in equation 95 gives the set of equations 

For the two-sublattice model, v = 2, and elimination of the Mi from equations 101 and 102 gives 

Al mard (5) has applied the method to the ferrimagnetic garnets, where the ionic distributions are known. He includes, to first order, the temperature dependence of the molecular field constants, n = no(l + yT), that was first formulated by N6el (472). The coefficient 7 10 4 is proportional to the coefficient of thermal ex- 

To determine the order disorder transition temperature, which is usually called the N6el temperature TV in antiferromagnets, but the 

Tc = (n/2) [(0 - C2py + 4CiC2]1/2 + Cxa + Crf (108) For an antiferromagnct with both sublattices identical, this reduces to 

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