Materials Data on Nb5O12F by Materials Project

Abstract

Nb5O12F crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. there are three inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with three equivalent NbO6 octahedra, corners with three NbO7 pentagonal bipyramids, and edges with two NbO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 14–30°. There are a spread of Nb–O bond distances ranging from 1.96–2.05 Å. In the second Nb5+ site, Nb5+ is bonded to seven O2- atoms to form NbO7 pentagonal bipyramids that share corners with two equivalent NbO6 octahedra, corners with two equivalent NbO7 pentagonal bipyramids, edges with two equivalent NbO6 octahedra, and edges with two equivalent NbO6F pentagonal bipyramids. The corner-sharing octahedral tilt angles are 26°. There are a spread of Nb–O bond distances ranging from 1.95–2.32 Å. In the third 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 NbO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 40–46°. There are a spread of Nb–O bond distances ranging from 1.95–2.26 Å. The Nb–F bond length is 2.29 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three Nb5+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three Nb5+ atoms. In the third O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. F1- is bonded in a distorted linear geometry to two equivalent Nb5+ atoms.