Materials Data on NaFeSnO4 by Materials Project

Abstract

NaFeSnO4 crystallizes in the orthorhombic Pmc2_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 2.48–2.70 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 2.44–2.69 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent SnO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent SnO6 octahedra. The corner-sharing octahedra tilt angles range from 50–56°. There are a spread of Fe–O bond distances ranging from 2.05–2.11 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent SnO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent SnO6 octahedra. The corner-sharing octahedra tilt angles range from 48–57°. There are a spread of Fe–O bond distances ranging from 2.06–2.09 Å. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with four equivalent FeO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent SnO6 octahedra. The corner-sharing octahedra tilt angles range from 48–57°. There are a spread of Sn–O bond distances ranging from 2.09–2.12 Å. In the second Sn4+ site, Sn4+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with four equivalent FeO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with two equivalent SnO6 octahedra. The corner-sharing octahedra tilt angles range from 50–56°. There are two shorter (2.09 Å) and four longer (2.12 Å) Sn–O bond lengths. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Na1+, one Fe3+, and two equivalent Sn4+ atoms to form a mixture of distorted edge and corner-sharing ONa2FeSn2 trigonal bipyramids. In the second O2- site, O2- is bonded to two equivalent Na1+, two equivalent Fe3+, and one Sn4+ atom to form distorted ONa2Fe2Sn trigonal bipyramids that share corners with two equivalent ONa2Fe2Sn square pyramids, corners with two equivalent ONa2FeSn2 trigonal bipyramids, an edgeedge with one ONa2Fe2Sn square pyramid, and edges with six ONa2FeSn2 trigonal bipyramids. In the third O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Fe3+, and two equivalent Sn4+ atoms. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, two equivalent Fe3+, and one Sn4+ atom. In the fifth O2- site, O2- is bonded to two equivalent Na1+, one Fe3+, and two equivalent Sn4+ atoms to form distorted ONa2FeSn2 trigonal bipyramids that share corners with four ONa2FeSn2 square pyramids, corners with seven ONa2FeSn2 trigonal bipyramids, edges with three ONa2FeSn2 square pyramids, and edges with two equivalent ONa2Fe2Sn trigonal bipyramids. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, two equivalent Fe3+, and one Sn4+ atom. In the seventh O2- site, O2- is bonded to two equivalent Na1+, one Fe3+, and two equivalent Sn4+ atoms to form a mixture of distorted edge and corner-sharing ONa2FeSn2 square pyramids. In the eighth O2- site, O2- is bonded to two equivalent Na1+, two equivalent Fe3+, and one Sn4+ atom to form distorted ONa2Fe2Sn square pyramids that share corners with four ONa2Fe2Sn trigonal bipyramids, edges with four ONa2FeSn2 square pyramids, and edges with three ONa2Fe2Sn trigonal bipyramids.