Curie-Weiss theory

The second-order ferroelectric transitions can be modeled using the Curie-Weiss theory of ferromagnetism. It is assumed that there is a local field that is proportional to the polarization or E-Loc = E + yP/so, where y is the constant of proportionality. For T>Tq, Equation 23.28 gives P = Np Eux /kT and the susceptibility is given by... 

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