Materials Data on Nb2(CoO3)3 by Materials Project

Abstract

Nb2(CoO3)3 crystallizes in the trigonal P3c1 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 nine CoO6 octahedra. The corner-sharing octahedra tilt angles range from 31–53°. There are three shorter (1.89 Å) and three longer (2.20 Å) Nb–O bond lengths. In the second Nb5+ site, Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (1.98 Å) and three longer (2.06 Å) Nb–O bond lengths. There are three inequivalent Co+2.67+ sites. In the first Co+2.67+ site, Co+2.67+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three equivalent NbO6 octahedra, corners with three equivalent CoO6 octahedra, and a faceface with one CoO6 octahedra. The corner-sharing octahedra tilt angles range from 31–43°. There is three shorter (1.87 Å) and three longer (2.00 Å) Co–O bond length. In the second Co+2.67+ site, Co+2.67+ is bonded to six O2- atoms to form distorted CoO6 octahedra that share corners with three equivalent NbO6 octahedra, edges with three equivalent CoO6 octahedra, and a faceface with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are three shorter (1.98 Å) and three longer (2.16 Å) Co–O bond lengths. In the third Co+2.67+ site, Co+2.67+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three equivalent NbO6 octahedra, corners with three equivalent CoO6 octahedra, and edges with three equivalent CoO6 octahedra. The corner-sharing octahedra tilt angles range from 43–47°. There are three shorter (2.06 Å) and three longer (2.15 Å) Co–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to one Nb5+ and three Co+2.67+ atoms to form a mixture of distorted edge and corner-sharing ONbCo3 trigonal pyramids. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Co+2.67+ atoms. In the third O2- site, O2- is bonded in a distorted T-shaped geometry to two Nb5+ and one Co+2.67+ atom.