Materials Data on BaNb4(FeO7)2 by Materials Project

Abstract

BaNb4(FeO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.79–3.06 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to four O2- atoms to form NbO4 tetrahedra that share corners with three equivalent FeO6 octahedra and a cornercorner with one NbO4 tetrahedra. The corner-sharing octahedra tilt angles range from 29–61°. There are a spread of Nb–O bond distances ranging from 1.85–1.95 Å. In the second Nb5+ site, Nb5+ is bonded to four O2- atoms to form NbO4 tetrahedra that share corners with three equivalent FeO6 octahedra and a cornercorner with one NbO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–49°. There are a spread of Nb–O bond distances ranging from 1.84–1.95 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six NbO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.07 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Nb5+ and one Fe3+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+, one Nb5+, and one Fe3+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Nb5+, and one Fe3+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Nb5+, and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Nb5+, and one Fe3+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Nb5+ and one Fe3+ atom.