Partition functions of two-dimensional Ising models -- A perspective from Gauss hypergeometric functions

Abstract

Employing heuristic susceptibility equations in conjunction with the well-known critical exponents, the magnetization and partition function for two-dimensional nearest neighbour Ising models are formulated in terms of the Gauss hypergeometric functions. The isomorphism existing between the Bragg-Williams approximation and the exact solution of Onsager is pointed out. The precise manner in which the critical exponents influence the partition functions is pointed out.