Electronic, magnetic and optical properties of double perovskite Sr2CuIrO6

The different magnetic ordering structures of double perovskite Sr2CuIrO6 have been calculated, and the C-type antiferromagnetic structure can be determined according to the lowest energy principle, the partial density of states and the spin magnetic moments. The antiferromagnetic structure of double perovskite Sr2CuIrO6 can be explained by the semicovalent-exchange mechanism. Cu2b and Ir2a atoms are antiferromagnetically coupled in the XY-plane through the magnetic exchange chains of $${\text{Cu}}_{{{\text{2b}}}}^{{1}} {\text{-O}}_{{{\text{8h}}}}^{{2}} {\text{-Ir}}_{{{\text{2a}}}}^{{2}}$$ and $${\text{Ir}}_{{{\text{2a}}}}^{{1}} {\text{-O}}_{{{\text{8h}}}}^{{1}} {\text{-Cu}}_{{{\text{2b}}}}^{{2}}$$ , while Cu2b and Ir2a atoms are ferromagnetically coupled along the Z-axis through the magnetic exchange chains of $${\text{ Ir}}_{{{\text{2a}}}}^{{1}} {\text{-O}}_{{{\text{4e}}}}^{{1}} {\text{-Cu}}_{{{\text{2b}}}}^{{1}}$$ and $${\text{Cu}}_{{{\text{2b}}}}^{{2}} {\text{-O}}_{{{\text{4e}}}}^{{2}} {\text{-Ir}}_{{{\text{2a}}}}^{{2}}$$ . The electronic structure calculated by the hybrid functional HSE06 indicates that double perovskite Sr2CuIrO6 is an antiferromagnetic semiconductor with an indirect band gap. The electron transitions from O-2p orbitals in the valence bands to Ir-5d orbitals in the conduction bands play an important role in the optical properties of double perovskite Sr2CuIrO6, and it has high absorption coefficient in the ultraviolet region.