Materials Data on Na2Fe3SbO8 by Materials Project

Abstract

Na2Fe3SbO8 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.40–2.72 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.41–2.78 Å. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent SbO6 octahedra, and edges with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 50–56°. There are a spread of Fe–O bond distances ranging from 2.02–2.32 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent SbO6 octahedra, and edges with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 47–57°. There are a spread of Fe–O bond distances ranging from 2.02–2.11 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four FeO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent SbO6 octahedra. The corner-sharing octahedra tilt angles range from 50–57°. There are a spread of Fe–O bond distances ranging from 1.96–2.21 Å. Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four FeO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent SbO6 octahedra. The corner-sharing octahedra tilt angles range from 47–56°. There are a spread of Sb–O bond distances ranging from 1.98–2.06 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to two Na1+, two equivalent Fe3+, and one Sb5+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to two Na1+ and three Fe3+ atoms. In the third O2- site, O2- is bonded to two equivalent Na1+, two equivalent Fe3+, and one Sb5+ atom to form distorted ONa2Fe2Sb trigonal bipyramids that share corners with two equivalent ONa2Fe3 square pyramids, an edgeedge with one ONa2Fe3 square pyramid, and edges with four ONa2Fe2Sb trigonal bipyramids. In the fourth O2- site, O2- is bonded to two equivalent Na1+, one Fe3+, and two equivalent Sb5+ atoms to form distorted ONa2FeSb2 trigonal bipyramids that share corners with two equivalent ONa2Fe3 square pyramids, an edgeedge with one ONa2Fe3 square pyramid, and edges with four ONa2Fe2Sb trigonal bipyramids. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Fe3+, and two equivalent Sb5+ atoms. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+ and three Fe3+ atoms. In the seventh O2- site, O2- is bonded to two equivalent Na1+ and three Fe3+ atoms to form distorted ONa2Fe3 square pyramids that share corners with two equivalent ONa2Fe2Sb trigonal bipyramids, edges with four ONa2Fe3 square pyramids, and an edgeedge with one ONa2Fe2Sb trigonal bipyramid. In the eighth O2- site, O2- is bonded to two equivalent Na1+ and three Fe3+ atoms to form ONa2Fe3 square pyramids that share corners with two equivalent ONa2FeSb2 trigonal bipyramids, edges with four ONa2Fe3 square pyramids, and an edgeedge with one ONa2FeSb2 trigonal bipyramid.