Exchange couplings calculation in Sr2CrNO6 (NÂ =Â Os, Ir) Double Perovskites: Monte Carlo simulation

Exchange couplings in Sr2CrNO6 (N = Os, Ir) Double Perovskites (DPs) have been calculated numerically by using a Monte Carlo Simulation (MCS) in the frame work of Ising model by means of a relation between internal energy per site and magnetization per site. Two model parameters α and α' have been proposed for Sr2CrOsO6 and Sr2CrIrO6, respectively. The exchange couplings have been computed by varying α and α' through a MCS to find their values corresponding to the transition temperature 725K specific to Sr2CrOsO6 and 884K specific to Sr2CrIrO6. The exchange couplings JCr−Os=−35.201meV, JCr−Cr=5.452meV and JOs−Os=14.873meV have been obtained for Sr2CrOsO6, while JCr−Ir=−24.464meV, JCr−Cr'=2.181meV and JIr−Ir=16.730meVhave been obtained for Sr2CrIrO6. Magnetization and magnetic susceptibility have been investigated in both compounds. Internal energy per site has been given.