Materials Data on Nb2CuO6 by Materials Project

Abstract

CuNb2O6 is Brookite-derived structured and crystallizes in the monoclinic P2_1/c 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 distorted NbO6 octahedra that share corners with two equivalent NbO6 octahedra and corners with four equivalent CuO6 octahedra. The corner-sharing octahedra tilt angles range from 47–55°. There are a spread of Nb–O bond distances ranging from 1.87–2.32 Å. In the second Nb5+ site, Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.84–2.30 Å. Cu2+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with four equivalent NbO6 octahedra and edges with two equivalent CuO6 octahedra. The corner-sharing octahedra tilt angles range from 51–55°. There are a spread of Cu–O bond distances ranging from 1.93–2.38 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Nb5+ and two equivalent Cu2+ atoms. In the second O2- site, O2- is bonded in a trigonal planar geometry to two Nb5+ and one Cu2+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two equivalent Cu2+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Cu2+ atom.