Critical distortion of Potts model

The critical distortion d/sub c/ of the Potts models on a number of lattices is shown to be related to the radius of convergence R of Mayer's series by d/sub c/=(q-1)R/(1+R). By using the matrix representation of Mayer's series, a recursive approach is applied to estimate R, and hence d/sub c/ for Ising models for which q=2.