Derivation of Low-Temperature Expansions for the Ising Model of a Ferromagnet and an Antiferromagnet

Abstract

Low-temperature expansions for the free energy of the Ising model of a ferromagnet and an antiferromagnet are derived for the more usual two- and three-dimensional lattices. The underlying enumerative problem is studied and a new method described that makes it possible to obtain more terms than available previously without undue labor.