Powder neutron diffraction of SrNbO2N at room temperature and 1.5 K.

The structure of strontium niobium dioxygen nitride, SrNbO2N, has been solved by powder neutron diffraction at room temperature and 1.5 K. SrNbO2N crystallizes in the tetragonal space group I4/mcm, with a = 5.7056 (4) and c = 8.1002 (9) A at room temperature, and a = 5.6938 (4) and c = 8.0974 (8) A at 1.5 K. The crystal structure is derived from the cubic perovskite archetype by a slight rotation of the Nb(O,N)6 octahedra with respect to the tetragonal axis. A partially ordered distribution of oxygen and nitrogen on the anionic sites was found.