Thermodynamic properties of the exactly solvable mixed spin-S and spin- Ising model with four-spin interactions on doubly decorated planar lattices

The exact solution of the doubly decorated Ising model with two- and four-spin interactions and crystal-field anisotropy is obtained using the generalized mapping transformation technique. Within this scheme, the exact relations for the phase boundaries, compensation points and spontaneous magnetization are derived for different planar lattices with the arbitrary values of the decorating spins. The particular attention has been paid to the investigation of the reentrant behaviour in the system. The region in which the reentrant behaviour and compensation phenomena occur in the system is studied in detail.