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Based on the density functional theory and the Monte Carlo Simulation (MCS), the structural, the electronic and the magnetic properties of Sr 2 TiMoO 6 double perovskite have been studied with (GGA), (GGA + U) and (GGA + U + SOC) approaches. The lattice parameter, the band structure and the electronic densities of states have been analyzed. Furthermore, the results show a half-metallic behavior of the compound with (GGA + U) . By the energy calculation, Sr 2 TiMoO 6 oxide shows an antiferromagnetic ordering. The exchange coupling of Sr 2 TiMoO 6 has been also computed in order to investigate the magnetic properties by using MCS in the framework of the Ising model. Interesting phenomena have been obtained such as the first-order transitions and multiple hysteresis loops. These results make Sr 2 TiMoO 6 a promising candidate for spintronic applications. [ABSTRACT FROM AUTHOR]

Based on the density functional theory and the Monte Carlo Simulation (MCS), the structural, the electronic and the magnetic properties of Sr 2 TiMoO 6 double perovskite have been studied with (GGA), (GGA + U) and (GGA + U + SOC) approaches. The lattice parameter, the band structure and the electronic densities of states have been analyzed. Furthermore, the results show a half-metallic behavior of the compound with (GGA + U) . By the energy calculation, Sr 2 TiMoO 6 oxide shows an antiferromagnetic ordering. The exchange coupling of Sr 2 TiMoO 6 has been also computed in order to investigate the magnetic properties by using MCS in the framework of the Ising model. Interesting phenomena have been obtained such as the first-order transitions and multiple hysteresis loops. These results make Sr 2 TiMoO 6 a promising candidate for spintronic applications. [ABSTRACT FROM AUTHOR]

The electronic and the magnetic properties of the double perovskite S r 2 C r W O 6 are studied by using ab-initio density functional theory (DFT) calculations with Generalized Gradient Approximation (GGA) and Monte Carlo simulation within the framework the Ising model. This compound is formed by two magnetic cubic sublattices, one occupied by Chromium C r 3 + with spin (S = 3 / 2) and the other occupied by Tungsten W 5 + with spin (σ = 1 / 2). The density of states (DOS) and the band structure of the compound are investigated. The results show the half metallic behavior of S r 2 C r W O 6 with a total magnetic moment equal to 2 μ B . The degeneracy removed from the orbital d of the Chromium by the octahedral crystal field was discussed. The exchange couplings C r − C r and W − W are ferromagnetic, while the super exchange coupling C r − O − W is antiferromagnetic. Concerning the Monte carlo study, it is seen that the system presents interesting phenomena. In particular, the compensation behavior, the first order transition and multiple hysteresis loops have been obtained. • The electronic and the magnetic properties of the double perovskite Sr 2 CrWO 6 are studied by using DFT and MCS. • The results show the half metallic behavior of Sr 2 CrWO 6 with a total magnetic moment equal to 2μ B. • The compensation behavior, the first order transition and multiple hysteresis loops have been obtained. [ABSTRACT FROM AUTHOR]

Anti-perovskite nitride material F e 3 A l N is studied by using the density functional theory with generalized gradient approximation (GGA+U) approaches and the Monte Carlo simulation in the framework of the Ising model. The parameter of the unit cell has been optimized, the electronic band structure, the electronic density of states and the magnetic moments of the compound are discussed. Based on the energy calculations, the exchange interactions and the magnetic anisotropy are calculated in order to perform the Monte Carlo simulation. Therefore the obtained Curie temperature T c =780 (K) of the compound is in agreement with the experimental one T c =770 (K). The magnetic and magnetocaloric properties are also investigated, the maximum entropy change and the RCP values are 3.355 J/Kg.K and 638 J/Kg for h=5T, respectively. Based on the hysteresis loops, the energy product BH was calculated. The obtained B H m a x is equal to 1.26 (MGOe) above the ambient temperature. These results show that the F e 3 A l N compound can be a good candidate for both information storage applications and magnetic refrigeration. • The magnetocaloric effect, electronic and magnetic properties of AlFe3N have been investigated. • Exchange coupling and magnetic anisotropy have been calculated. • Magnetic energy product of AlFe3N has been discussed. • Based on its relative cooling power, AlFe3N is a good candidate for the magnetic refrigeration. • Based on the magnetic energy product, AlFe3N is a hard magnet material. [ABSTRACT FROM AUTHOR]

Using the Monte Carlo method, we have studied the effect of the Hamiltonian parameters (the exchange couplings, the crystal and the magnetic fields) on the magnetizations, the phase diagrams and the hysteresis behavior of a hexagonal ferromagnetic or ferrimagnetic Ising core/shell nanoparticle with mixed spin-5/2 and spin-2. Interesting phenomena have been shown. In particular, the system exhibits the first order transition, the compensation temperature and the compensation crystal field. In addition, the nanoparticle presents single, double, triple and quintuple hysteresis loops. • MCS has been used to study the magnetic properties of a mixed spin-(5/2, 2) Ising core/shell nanoparticle. • The system presents a special point at which four first order transition lines are linked. • The compensation behavior and multiple hysteresis loops have been observed. [ABSTRACT FROM AUTHOR]