Ground state phase diagrams for the mixed Ising 2 and 5/2 spin model

Abstract

We investigate the behavior of ground state phase diagrams of a mixed Ising spins model on a bipartite square lattice of spins SiA=2 and σjB=5/2. The proposed Hamiltonian includes coupling to first and second neighbors, and crystal field interactions between sublattices. In the phase diagrams, according to the combination of the parameters in the Hamiltonian, multiphase points, disordered regions, and various structures are presented. Phase diagrams of the ground state are useful to check the reliability of the numerical results for the phase diagrams at finite temperature and allow exploring regions where important magnetic behaviors could arise.