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DOE OSTI · 1284250

Materials Data on Ba6Nb5S17 by Materials Project

Abstract

Ba6Nb5S17 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven S2- atoms. There are a spread of Ba–S bond distances ranging from 3.32–3.64 Å. In the second Ba2+ site, Ba2+ is bonded to twelve S2- atoms to form BaS12 cuboctahedra that share corners with four NbS6 octahedra, a cornercorner with one NbS5 square pyramid, faces with two equivalent BaS12 cuboctahedra, faces with four NbS6 octahedra, and a faceface with one NbS5 square pyramid. The corner-sharing octahedra tilt angles range from 13–23°. There are a spread of Ba–S bond distances ranging from 3.35–3.60 Å. In the third Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven S2- atoms. There are a spread of Ba–S bond distances ranging from 3.28–3.67 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven S2- atoms. There are a spread of Ba–S bond distances ranging from 3.32–3.64 Å. In the fifth Ba2+ site, Ba2+ is bonded to twelve S2- atoms to form BaS12 cuboctahedra that share corners with four NbS6 octahedra, a cornercorner with one NbS5 square pyramid, faces with two equivalent BaS12 cuboctahedra, faces with four NbS6 octahedra, and a faceface with one NbS5 square pyramid. The corner-sharing octahedra tilt angles range from 19–28°. There are a spread of Ba–S bond distances ranging from 3.37–3.65 Å. In the sixth Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to eleven S2- atoms. There are a spread of Ba–S bond distances ranging from 3.37–3.55 Å. There are five inequivalent Nb+4.40+ sites. In the first Nb+4.40+ site, Nb+4.40+ is bonded to six S2- atoms to form NbS6 octahedra that share corners with two BaS12 cuboctahedra, faces with two BaS12 cuboctahedra, a faceface with one NbS6 octahedra, and a faceface with one NbS5 square pyramid. There are a spread of Nb–S bond distances ranging from 2.44–2.59 Å. In the second Nb+4.40+ site, Nb+4.40+ is bonded to five S2- atoms to form distorted NbS5 square pyramids that share corners with two BaS12 cuboctahedra, faces with two BaS12 cuboctahedra, and a faceface with one NbS6 octahedra. There are a spread of Nb–S bond distances ranging from 2.30–2.57 Å. In the third Nb+4.40+ site, Nb+4.40+ is bonded to six S2- atoms to form NbS6 octahedra that share corners with two BaS12 cuboctahedra, faces with two BaS12 cuboctahedra, and faces with two NbS6 octahedra. There are a spread of Nb–S bond distances ranging from 2.43–2.56 Å. In the fourth Nb+4.40+ site, Nb+4.40+ is bonded to six S2- atoms to form distorted NbS6 octahedra that share corners with two BaS12 cuboctahedra, faces with two BaS12 cuboctahedra, and a faceface with one NbS6 octahedra. There are a spread of Nb–S bond distances ranging from 2.31–2.80 Å. In the fifth Nb+4.40+ site, Nb+4.40+ is bonded to six S2- atoms to form NbS6 octahedra that share corners with two BaS12 cuboctahedra, faces with two BaS12 cuboctahedra, and faces with two NbS6 octahedra. There are a spread of Nb–S bond distances ranging from 2.43–2.55 Å. There are seventeen inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to four Ba2+ and one Nb+4.40+ atom. In the second S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the third S2- site, S2- is bonded in a distorted single-bond geometry to four Ba2+ and one Nb+4.40+ atom. In the fourth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the fifth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the sixth S2- site, S2- is bonded in a 1-coordinate geometry to four Ba2+ and one Nb+4.40+ atom. In the seventh S2- site, S2- is bonded in a distorted single-bond geometry to four Ba2+ and one Nb+4.40+ atom. In the eighth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the ninth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the tenth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the eleventh S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the twelfth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the thirteenth S2- site, S2- is bonded in a distorted single-bond geometry to four Ba2+ and one Nb+4.40+ atom. In the fourteenth S2- site, S2- is bonded in a 1-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the fifteenth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the sixteenth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms. In the seventeenth S2- site, S2- is bonded in a 6-coordinate geometry to four Ba2+ and two Nb+4.40+ atoms.

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2020-05-01. Materials Data on Ba6Nb5S17 by Materials Project. https://doi.org/10.17188/1284250

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