Materials Data on Nb3O7F by Materials Project
Nb3O7F crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent NbO6F pentagonal bipyramids, and edges with two equivalent NbO6F pentagonal bipyramids. The corner-sharing octahedral tilt angles are 0°. There is two shorter (1.96 Å) and four longer (2.03 Å) Nb–O bond length. In the second Nb5+ site, Nb5+ is bonded to six O2- and one F1- atom to form NbO6F pentagonal bipyramids that share corners with two equivalent NbO6 octahedra, corners with three equivalent NbO6F pentagonal bipyramids, an edgeedge with one NbO6 octahedra, and edges with two equivalent NbO6F pentagonal bipyramids. The corner-sharing octahedral tilt angles are 36°. There are two shorter (1.96 Å) and four longer (2.10 Å) Nb–O bond lengths. The Nb–F bond length is 2.16 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. F1- is bonded in a distorted linear geometry to two equivalent Nb5+ atoms.