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DOE OSTI · 1206610

Materials Data on Ba9Nb10O30 by Materials Project

Abstract

Ba9Nb10O30 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with eleven BaO12 cuboctahedra, faces with five BaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.89–2.96 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with eleven BaO12 cuboctahedra, faces with five BaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.89–2.95 Å. In the third Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with eleven BaO12 cuboctahedra, faces with five BaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.90–2.95 Å. In the fourth Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with ten BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.88–2.93 Å. In the fifth Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with ten BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, and faces with eight NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.88–2.94 Å. There are five inequivalent Nb+4.20+ sites. In the first Nb+4.20+ site, Nb+4.20+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with seven BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Nb–O bond distances ranging from 2.04–2.10 Å. In the second Nb+4.20+ site, Nb+4.20+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with seven BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–4°. There are a spread of Nb–O bond distances ranging from 2.04–2.10 Å. In the third Nb+4.20+ site, Nb+4.20+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with seven BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–4°. There are a spread of Nb–O bond distances ranging from 2.03–2.10 Å. In the fourth Nb+4.20+ site, Nb+4.20+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with seven BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–4°. There are a spread of Nb–O bond distances ranging from 2.03–2.11 Å. In the fifth Nb+4.20+ site, Nb+4.20+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.06 Å) and four longer (2.07 Å) Nb–O bond lengths. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to three Ba2+ and two Nb+4.20+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to three Ba2+ and two Nb+4.20+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to three Ba2+ and two Nb+4.20+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to three Ba2+ and two Nb+4.20+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the eighth O2- site, O2- is bonded in a distorted linear geometry to three Ba2+ and two Nb+4.20+ atoms. In the ninth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the tenth O2- site, O2- is bonded in a distorted linear geometry to three Ba2+ and two Nb+4.20+ atoms. In the eleventh O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the twelfth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Nb+4.20+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Nb+4.20+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Nb+4.20+ atoms.

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2020-04-30. Materials Data on Ba9Nb10O30 by Materials Project. https://doi.org/10.17188/1206610

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