Materials Data on NaTiFeO4 by Materials Project

NaFeTiO4 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 2.41–2.64 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 2.40–2.64 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four equivalent FeO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 49–54°. There is three shorter (1.99 Å) and three longer (2.00 Å) Ti–O bond length. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four equivalent FeO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–55°. There are a spread of Ti–O bond distances ranging from 1.96–2.01 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 TiO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–55°. There are a spread of Fe–O bond distances ranging from 2.03–2.11 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent TiO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 49–54°. There are five shorter (2.05 Å) and one longer (2.07 Å) Fe–O bond lengths. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, two equivalent Ti4+, and one Fe3+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Ti4+, and two equivalent Fe3+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, two equivalent Ti4+, and one Fe3+ atom. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Ti4+, and two equivalent Fe3+ atoms. In the fifth O2- site, O2- is bonded to two equivalent Na1+, two equivalent Ti4+, and one Fe3+ atom to form a mixture of distorted edge and corner-sharing ONa2Ti2Fe square pyramids. In the sixth O2- site, O2- is bonded to two equivalent Na1+, one Ti4+, and two equivalent Fe3+ atoms to form distorted edge-sharing ONa2TiFe2 square pyramids. In the seventh O2- site, O2- is bonded to two equivalent Na1+, two equivalent Ti4+, and one Fe3+ atom to form a mixture of distorted edge and corner-sharing ONa2Ti2Fe trigonal bipyramids. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Ti4+, and two equivalent Fe3+ atoms.