Half-metallic antiferromagnetic behavior of double perovskite Sr2OsMoO6: First principle calculations

Electronic structure calculations based on density functional theory within the generalized gradient approximation for double perovskite Sr2FeMoO6 and Sr2OsMoO6 have been performed using the accurate full potential augmented spherical wave method. By substituting Fe atoms by Os in the double perovskite structure oxides we have shown that it is possible to realize half-metallic antiferromagnets with 100% spin polarization of the conduction electrons crossing the Fermi level, without showing a net magnetization. To support our results, GGA+U electronic structure calculations have been performed showing that the half-metallic antiferromagnetic state still persists. We conclude that the origin of the antiferromagnetism in Sr2OsMoO6 may be attributed to both superexchange and generalized double exchange mechanisms via the B(3d,5d)–O(2p)–B′(4d) coupling. - Highlights: • Electronic structure of double perovskite Sr2FeMoO6 and Sr2OsMoO6 has been studied. • A density functional theory within GGA and GGA+U approximations was performed. • Sr2OsMoO6 is a HM-AFM material with 100% polarization and vanishing magnetization. • The antiferromagnetism is attributed to super-exchange and double exchange mechanisms