Theoretical and experimental studies of structural characteristics, magnetic response and electronic properties of Sr2 FeMnO6 complex perovskite

We report synthesis of the Sr2FeMnO6 complex perovskite and crystalline structure study by x-ray diffraction experiments, using the Rietveld refinement method. Ab initio calculations of density of states and electronic structure for this manganite-like material were carried out by the Density Functional Theory and the Linearized Augmented Plane Waves method for both up and down spin orientations. Magnetic character of system was introduced by the spin polarization into the Generalized Gradient Approximation. Our calculation for this complex perovskite material predicts the occurrence of a magnetic moment of 2.54 mu LB. This result is in agreement with experimental Curie-Weiss fittings, which give a value of 2.8 mu B. Our theoretical calculations in the paramagnetic ground state show that this compound has a metallic behavior. From energy-volume DFT calculations, we determined the optimal structure for the Sr2FeMnO6 double perovskite material, by using the space group. A comparative analysis between structural properties predicted by DFT and the structural ordering found from the Rietveld refinement method is performed with a matching of 98.6%.