Materials Data on SrNb4O14 by Materials Project
SrNb4O14 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Sr is bonded to eight O atoms to form SrO8 hexagonal bipyramids that share edges with six equivalent NbO6 octahedra. There are six shorter (2.69 Å) and two longer (2.72 Å) Sr–O bond lengths. There are two inequivalent Nb sites. In the first Nb site, Nb is bonded to six equivalent O atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 37°. All Nb–O bond lengths are 2.00 Å. In the second Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and edges with two equivalent SrO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 37–40°. All Nb–O bond lengths are 2.00 Å. There are three inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to one Sr and two equivalent Nb atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two Nb atoms. In the third O site, O is bonded in a single-bond geometry to one Sr atom.