Magnetic order and electronic structure of the 5d3 double perovskite Sr2ScOsO6

The magnetic susceptibility, crystal and magnetic structures, and electronic structure of the double perovskite Sr2ScOsO6 are reported. Using both neutron and x-ray powder diffraction we find that the crystal structure is monoclinic P2(1)/n from 3.5 to 300 K. Magnetization measurements indicate an antiferromagnetic transition at T-N = 92 K, one of the highest transition temperatures of any double perovskite hosting only one magnetic ion. Type I antiferromagnetic order is determined by neutron powder diffraction, with an Os moment of only 1.6(1)mu(B), close to half the spin-only value for a crystal field split 5d electron state with a t(2g)(3) ground state. Density functional calculations show that this reduction is largely the result of strong Os-O hybridization, with spin-orbit coupling responsible for only a similar to 0.1 mu(B) reduction in the moment.