Materials Data on Nb2CuO6 by Materials Project
CuNb2O6 is Brookite-derived structured and crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four equivalent NbO6 octahedra, corners with four equivalent CuO6 octahedra, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 33–63°. There are a spread of Nb–O bond distances ranging from 1.81–2.32 Å. Cu2+ is bonded to six O2- atoms to form distorted CuO6 octahedra that share corners with eight equivalent NbO6 octahedra and edges with two equivalent CuO6 octahedra. The corner-sharing octahedra tilt angles range from 33–63°. There are a spread of Cu–O bond distances ranging from 1.95–2.58 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to three equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Nb5+ and two equivalent Cu2+ atoms. In the third O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Nb5+ and one Cu2+ atom.