Materials Data on NaOsSe2 by Materials Project

Abstract

NaOsSe2 crystallizes in the cubic F-43m space group. The structure is three-dimensional. Na1+ is bonded to ten Se2- atoms to form distorted NaSe10 tetrahedra that share corners with six equivalent NaSe10 tetrahedra, corners with twelve equivalent OsSe4 tetrahedra, corners with twelve equivalent SeNa4Se4 tetrahedra, faces with four equivalent OsSe4 tetrahedra, faces with four equivalent SeNa4Se4 tetrahedra, and faces with twelve equivalent NaSe10 tetrahedra. There are four shorter (2.87 Å) and six longer (3.31 Å) Na–Se bond lengths. Os3+ is bonded to four equivalent Se2- atoms to form OsSe4 tetrahedra that share corners with four equivalent SeNa4Se4 tetrahedra, corners with twelve equivalent NaSe10 tetrahedra, corners with twelve equivalent OsSe4 tetrahedra, edges with six equivalent SeNa4Se4 tetrahedra, and faces with four equivalent NaSe10 tetrahedra. All Os–Se bond lengths are 2.87 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to six equivalent Na1+, four equivalent Os3+, and four equivalent Se2- atoms. All Se–Se bond lengths are 2.87 Å. In the second Se2- site, Se2- is bonded to four equivalent Na1+ and four equivalent Se2- atoms to form distorted SeNa4Se4 tetrahedra that share corners with four equivalent OsSe4 tetrahedra, corners with twelve equivalent NaSe10 tetrahedra, edges with six equivalent OsSe4 tetrahedra, edges with twelve equivalent SeNa4Se4 tetrahedra, and faces with four equivalent NaSe10 tetrahedra.