Exact solution for a layered two-dimensional Ising lattice
Glazman L.I., Tsukernik V.M.
The free energy is calculated for the Ising model with three independent coupling constants /„ I2, and 73, respectively, along the columns and rows with numbers of different parity. The low-temperature properties of the model for different ratios of /„ I2, and I3 and the existence conditions of the phase transition are analyzed.