Magnetic properties of the quaternary alloy with the mixtures of integer and half-integer spins

The ferrimagnetic-ferromagnetic-ferrimagnetic quaternary alloy consisting of the spins S-i(A) = 1, S-j(B) = 3/2, S-j(C) = 5/2 and S-j(D) = 2 in the form of AB(p)C(q)D(r) with B, C and D being the possible nearest-neighbors of A with the probabilities p, q and r, respectively, is investigated in terms of the mean field theory (MFT) based on the Bogoliubov inequality for free energy. The thermal behaviors of magnetizations belonging to the individual spins and total magnetization are examined in detail to map the possible phase diagrams on various planes. It was found that the model only exhibits second-order phase transitions in addition to one compensation temperature for appropriate values of the system parameters. In order to support the existence of the compensation temperatures, we have also carried out the Monte Carlo (MC) simulations and an agreement was shown with the predicted result of the MFT approach. We have also analyzed the effects of the bilinear interaction parameter between type-A atoms J(AA) and the exchange interaction parameter ratio R =J(AX)/vertical bar J(AB)|vertical bar(J(AX) is the bilinear interaction parameter between type-A atoms and type-X atoms with X = C or D) on compensation temperatures. Our findings are compared to those reported in the literature and suitable agreements are observed.