Exact results of a mixed spin - 1 / 2 and spin - S Ising model on a bathroom tile ( 4 - 8 ) lattice : effect of uniaxial single - ion anisotropy ⋆

Effect of uniaxial single-ion anisotropy upon magnetic properties of a mixed spin1/2 and spin-S (S ≥ 1) Ising model on a bathroom tile (4-8) lattice is examined within the framework of an exact star-triangle mapping transformation. The particular attention is focused on the phase diagrams established for several values of the quantum spin number S. It is shown that the mixed-spin bathroom tile lattice exhibits very similar phase boundaries as the mixed-spin honeycomb lattice whose critical points are merely slightly enhanced with respect to the former ones. The influence of uniaxial single-ion anisotropy upon the total magnetization vs. temperature dependence is particularly investigated as well.