Anomalous specific heat of dipolar spin glasses and ferroelectrics

We show that for a random Ising model with 1/R3 interactions, the probability distribution of molecular field p(H) goes to zero as H tends to zero. We suggest that p(H) ∼ H 1 2 for small H. Monte Carlo calculations of p(H) for the model are performed with results consistent with this suggestion. These results are used to explain the anomalous T 3 2 specific heat observed in alkali halides containing off-center ions, and in ferroelectrics. © 1978.