Materials Data on Li2NbOF5 by Materials Project
Li2NbOF5 is zeta iron carbide-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Li1+ is bonded to one O2- and five F1- atoms to form LiOF5 octahedra that share corners with six equivalent NbOF5 octahedra and edges with three equivalent LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 41–52°. The Li–O bond length is 2.07 Å. There are a spread of Li–F bond distances ranging from 2.00–2.13 Å. Nb5+ is bonded to one O2- and five F1- atoms to form NbOF5 octahedra that share corners with twelve equivalent LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 41–52°. The Nb–O bond length is 1.78 Å. There are four shorter (2.00 Å) and one longer (2.15 Å) Nb–F bond lengths. O2- is bonded in a 3-coordinate geometry to two equivalent Li1+ and one Nb5+ atom. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to two equivalent Li1+ and one Nb5+ atom. In the second F1- site, F1- is bonded in a distorted T-shaped geometry to two equivalent Li1+ and one Nb5+ atom. In the third F1- site, F1- is bonded in a distorted T-shaped geometry to two equivalent Li1+ and one Nb5+ atom.