Materials Data on Na4Br2O by Materials Project

Abstract

Na4OBr2 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to one O2- and five equivalent Br1- atoms to form a mixture of distorted edge and corner-sharing NaBr5O octahedra. The corner-sharing octahedral tilt angles are 0°. The Na–O bond length is 2.29 Å. There are one shorter (2.97 Å) and four longer (3.23 Å) Na–Br bond lengths. In the second Na1+ site, Na1+ is bonded in a distorted linear geometry to two equivalent O2- and four equivalent Br1- atoms. Both Na–O bond lengths are 2.28 Å. All Na–Br bond lengths are 3.23 Å. O2- is bonded to six Na1+ atoms to form corner-sharing ONa6 octahedra. The corner-sharing octahedral tilt angles are 0°. Br1- is bonded in a 9-coordinate geometry to nine Na1+ atoms.