Materials Data on Nb2OF8 by Materials Project
Nb2OF8 crystallizes in the monoclinic P2/c space group. The structure is one-dimensional and consists of two Nb2OF8 ribbons oriented in the (1, 0, 0) direction. there are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to one O2- and five F1- atoms to form corner-sharing NbOF5 octahedra. The corner-sharing octahedra tilt angles range from 1–45°. The Nb–O bond length is 2.12 Å. There are a spread of Nb–F bond distances ranging from 1.88–2.13 Å. In the second Nb5+ site, Nb5+ is bonded to one O2- and five F1- atoms to form a mixture of distorted corner and face-sharing NbOF5 octahedra. The corner-sharing octahedral tilt angles are 1°. The Nb–O bond length is 1.79 Å. There are a spread of Nb–F bond distances ranging from 1.88–2.22 Å. O2- is bonded in a distorted linear geometry to two Nb5+ atoms. There are nine inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ atoms. In the second F1- site, F1- is bonded in a single-bond geometry to one Nb5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Nb5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one Nb5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one Nb5+ atom. In the sixth F1- site, F1- is bonded in a distorted L-shaped geometry to two equivalent Nb5+ atoms. In the seventh F1- site, F1- is bonded in a single-bond geometry to one Nb5+ atom. In the eighth F1- site, F1- is bonded in a single-bond geometry to one Nb5+ atom. In the ninth F1- site, F1- is bonded in a water-like geometry to two equivalent Nb5+ atoms.