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DOE OSTI · 1266085

Materials Data on Ba9(NbN6)2 by Materials Project

Abstract

Ba9(NbN6)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to seven N+2.33- atoms. There are a spread of Ba–N bond distances ranging from 2.70–3.29 Å. In the second Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven N+2.33- atoms. There are a spread of Ba–N bond distances ranging from 2.83–3.35 Å. In the third Ba2+ site, Ba2+ is bonded in a 4-coordinate geometry to eight N+2.33- atoms. There are a spread of Ba–N bond distances ranging from 2.62–3.35 Å. In the fourth Ba2+ site, Ba2+ is bonded to five N+2.33- atoms to form distorted BaN5 trigonal bipyramids that share corners with two BaN6 octahedra, corners with two NbN4 tetrahedra, corners with four BaN5 trigonal bipyramids, edges with four BaN6 octahedra, an edgeedge with one NbN4 tetrahedra, and an edgeedge with one BaN5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 77–87°. There are a spread of Ba–N bond distances ranging from 2.71–3.29 Å. In the fifth Ba2+ site, Ba2+ is bonded to five N+2.33- atoms to form distorted BaN5 trigonal bipyramids that share corners with two BaN6 octahedra, corners with four NbN4 tetrahedra, a cornercorner with one BaN5 trigonal bipyramid, edges with two BaN6 octahedra, and an edgeedge with one BaN5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 16–100°. There are a spread of Ba–N bond distances ranging from 2.71–3.03 Å. In the sixth Ba2+ site, Ba2+ is bonded to six N+2.33- atoms to form distorted BaN6 octahedra that share corners with two equivalent BaN6 octahedra, a cornercorner with one NbN4 tetrahedra, edges with two equivalent BaN6 octahedra, an edgeedge with one NbN4 tetrahedra, and edges with four BaN5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 13–19°. There are a spread of Ba–N bond distances ranging from 2.74–3.13 Å. In the seventh Ba2+ site, Ba2+ is bonded to six N+2.33- atoms to form distorted BaN6 octahedra that share a cornercorner with one BaN6 octahedra, a cornercorner with one NbN4 tetrahedra, corners with two BaN5 trigonal bipyramids, edges with three BaN6 octahedra, an edgeedge with one NbN4 tetrahedra, and edges with three BaN5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 37°. There are a spread of Ba–N bond distances ranging from 2.57–3.25 Å. In the eighth Ba2+ site, Ba2+ is bonded to six N+2.33- atoms to form distorted BaN6 octahedra that share corners with three BaN6 octahedra, a cornercorner with one NbN4 tetrahedra, corners with two BaN5 trigonal bipyramids, edges with two BaN6 octahedra, edges with two NbN4 tetrahedra, and edges with three BaN5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 13–37°. There are a spread of Ba–N bond distances ranging from 2.87–3.17 Å. In the ninth Ba2+ site, Ba2+ is bonded to five N+2.33- atoms to form distorted BaN5 trigonal bipyramids that share corners with four NbN4 tetrahedra, corners with three equivalent BaN5 trigonal bipyramids, and edges with four BaN6 octahedra. There are a spread of Ba–N bond distances ranging from 2.65–3.28 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to four N+2.33- atoms to form NbN4 tetrahedra that share corners with three BaN6 octahedra, corners with five BaN5 trigonal bipyramids, an edgeedge with one BaN6 octahedra, and an edgeedge with one BaN5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 56–85°. There are a spread of Nb–N bond distances ranging from 1.97–2.03 Å. In the second Nb5+ site, Nb5+ is bonded to four N+2.33- atoms to form NbN4 tetrahedra that share corners with five BaN5 trigonal bipyramids and edges with three BaN6 octahedra. There are a spread of Nb–N bond distances ranging from 1.96–2.01 Å. There are twelve inequivalent N+2.33- sites. In the first N+2.33- site, N+2.33- is bonded in a 5-coordinate geometry to four Ba2+ and one Nb5+ atom. In the second N+2.33- site, N+2.33- is bonded in a 5-coordinate geometry to four Ba2+ and one Nb5+ atom. In the third N+2.33- site, N+2.33- is bonded in a 1-coordinate geometry to five Ba2+ and one Nb5+ atom. In the fourth N+2.33- site, N+2.33- is bonded to six Ba2+ atoms to form a mixture of corner and edge-sharing NBa6 octahedra. The corner-sharing octahedra tilt angles range from 20–24°. In the fifth N+2.33- site, N+2.33- is bonded in a 6-coordinate geometry to five Ba2+ and one Nb5+ atom. In the sixth N+2.33- site, N+2.33- is bonded in a 6-coordinate geometry to five Ba2+ and one Nb5+ atom. In the seventh N+2.33- site, N+2.33- is bonded in a 1-coordinate geometry to five Ba2+ and one Nb5+ atom. In the eighth N+2.33- site, N+2.33- is bonded to five Ba2+ and one Nb5+ atom to form distorted NBa5Nb octahedra that share corners with two equivalent NBa6 octahedra and edges with three NBa5Nb octahedra. The corner-sharing octahedra tilt angles range from 20–24°. In the ninth N+2.33- site, N+2.33- is bonded in a 6-coordinate geometry to five Ba2+ and one Nb5+ atom. In the tenth N+2.33- site, N+2.33- is bonded in a 4-coordinate geometry to four Ba2+ and one N+2.33- atom. The N–N bond length is 1.19 Å. In the eleventh N+2.33- site, N+2.33- is bonded in a 6-coordinate geometry to five Ba2+ and one N+2.33- atom. The N–N bond length is 1.19 Å. In the twelfth N+2.33- site, N+2.33- is bonded in a 2-coordinate geometry to two Ba2+ and two N+2.33- atoms.

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2020-07-15. Materials Data on Ba9(NbN6)2 by Materials Project. https://doi.org/10.17188/1266085

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