CLUSTER-VARIATION-PADE-APPROXIMANTS METHOD AND THE CRITICAL EXPONENTSOF THE FCC ISING-MODEL

We report results of the application of a recently proposed technique, which combines the cluster variation method (CVM) and Pade approximan ts, to the analysis of the critical behavior of the face-centered-cubi c Ising model. The highest-order CVM approximation ever considered for this lattice is used to estimate magnetization and susceptibility, wh ich are then analyzed by means of Dlog Pade approximants in order to e xtract information about the critical behavior, taking also into accou nt the effects of confluent singularities. Our results are in good agr eement with the most recent simulation and series expansion estimates and require a remarkably small numerical effort.