A comprehensive investigation of the electronic and magnetic properties of NaOsO${}_3$ has been made using first-principle calculations in order to understand the importance of Coulomb interaction, spin-orbit coupling, and magnetic order in its temperature-induced and magnetic-related metal-insulator transition. It is found that its electronic structure near the Fermi energy is dominated by strongly hybridized Os 5$d$ and O 2$p$ states. Despite of the large strength of spin-orbit coupling, it has only small effect on the electronic and magnetic properties of NaOsO${}_3$. On the other hand, the on-site Coulomb repulsion affects the band structure significantly, but a reasonable $U$ alone cannot open a band gap. Its magnetism is itinerant, and the magnetic configuration plays an important role in determining the electronic structure. Its ground state is of a G-type antiferromagnet, and it is the combined effect of $U$ and magnetic configuration that results in the insulating behavior of NaOsO${}_3$.

• Received 15 January 2012

DOI:https://doi.org/10.1103/PhysRevB.85.174424