Mechanical Stability, Magnetic and Electronic Properties of Sr1-xBaxFeO3: DFT+U Study
A. Rahmani, K. Driss Khodja, B. Amrani
Centre de Microscopie Electronique, Département de Physique, Université Oran 1, Oran, Algeria
Full Text PDF
We provide a thorough study of the structural, elastic, electronic and magnetic properties of the perovskite solid solution of Sr1-xBaxFeO3 within the framework of density functional theory (DFT), using the full-potential linearized augmented planewave plus local orbital FP-(L)APW+lo method. The found results provide predictions for the mixed perovskite solid solution Sr1-xBaxFeO3 (x=0.25, 0.5, 0.75) for which no experimental or theoretical data are presently available. These compounds were supposed to have a cubic ferromagnetic structure for all xcompositions. The GGA-PBE functional was chosen for the prediction of the structural properties, in particular the lattice parameter, the bulk modulus and its pressure derivative as well as the cohesive energy. For testing the mechanical stability of the Sr1-xBaxFeO3 compounds, we have studied their elastic constants and it has been found that these compounds are mechanically stable in their cubic perovskite structure. Several parameters related to the elastic constants have also been predicted, in particular Young's modulus, the shear modulus, Poisson's ratio, the anisotropic factor and the Debye temperature (θD). For the correct treatment of the high correlation of 3d-iron electrons, the Hubbard correction and TB-mBJ potential were added to the GGA-PBE functional for the analysis of the electronic and magnetic properties of Sr1-xBaxFeO3. It has been found that they are half-metals with a total magnetic moment of ~4μB

DOI:10.12693/APhysPolA.138.469
topics: Sr1-xBaxFeO3, DFT, GGA+U, TB-mBJ potential, elastic constants, half-metallic