High-Temperature Series Expansion of Susceptibility of the Ising Model with First and Second Neighbour Interactions on the Square Lattice

Chin-Tung Tseng；Keh-Ying Lin

Chinese Journal of Physics

34卷5期（1996 / 10 / 01）

1254 - 1260

英文

We have calculated exactly the high-temperature series expansion of the susceptibility of the Ising model with first and second neighbour interactions on the square lattice up to the 12th order by computer. Oitmaa computed the same series expansion up to the 11th order and his result agrees with ours except that his last term is slightly different from ours. We use the Padé approximants to estimate the critical exponent γ. The estimated value of 1.69 is about 3% smaller than the exact value of 1.75 for Ising model on the square lattice with first neighbour interactions only.