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DOE OSTI · 1284811

Materials Data on Ba3La9Mg7Nb5O36 by Materials Project

Abstract

Ba3Mg7La9Nb5O36 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with seven BaO12 cuboctahedra, faces with four LaO12 cuboctahedra, faces with four MgO6 octahedra, and faces with four NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.84–3.02 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with two equivalent LaO12 cuboctahedra, corners with ten BaO12 cuboctahedra, faces with six LaO12 cuboctahedra, faces with four MgO6 octahedra, and faces with four NbO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.85–2.89 Å. There are five inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four NbO6 octahedra, a faceface with one BaO12 cuboctahedra, and faces with three LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 5–13°. There are a spread of Mg–O bond distances ranging from 2.01–2.07 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six NbO6 octahedra, faces with three BaO12 cuboctahedra, and faces with four LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are a spread of Mg–O bond distances ranging from 2.04–2.08 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six NbO6 octahedra, faces with four BaO12 cuboctahedra, and faces with four LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Mg–O bond distances ranging from 2.05–2.07 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four equivalent NbO6 octahedra, and faces with two equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Mg–O bond distances ranging from 1.99–2.06 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra and faces with two equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Mg–O bond distances ranging from 1.97–2.10 Å. There are six inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.43–3.02 Å. In the second La3+ site, La3+ is bonded to twelve O2- atoms to form distorted LaO12 cuboctahedra that share corners with seven LaO12 cuboctahedra, faces with two equivalent LaO12 cuboctahedra, faces with four BaO12 cuboctahedra, faces with four MgO6 octahedra, and faces with four NbO6 octahedra. There are a spread of La–O bond distances ranging from 2.59–3.01 Å. In the third La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with ten LaO12 cuboctahedra, faces with six BaO12 cuboctahedra, faces with four MgO6 octahedra, and faces with four NbO6 octahedra. There are a spread of La–O bond distances ranging from 2.73–3.00 Å. In the fourth La3+ site, La3+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of La–O bond distances ranging from 2.61–3.10 Å. In the fifth La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with three equivalent LaO12 cuboctahedra, corners with five BaO12 cuboctahedra, faces with two equivalent LaO12 cuboctahedra, faces with three NbO6 octahedra, and faces with five MgO6 octahedra. There are a spread of La–O bond distances ranging from 2.71–2.97 Å. In the sixth La3+ site, La3+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of La–O bond distances ranging from 2.60–3.10 Å. There are three inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six MgO6 octahedra, a faceface with one BaO12 cuboctahedra, and faces with three LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 5–13°. There are a spread of Nb–O bond distances ranging from 1.98–2.03 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six MgO6 octahedra, faces with three BaO12 cuboctahedra, and faces with four LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are a spread of Nb–O bond distances ranging from 1.98–2.04 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six MgO6 octahedra, faces with four BaO12 cuboctahedra, and faces with four LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Nb–O bond distances ranging from 1.97–2.03 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to one Ba2+, one Mg2+, two La3+, and one Nb5+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to one Ba2+, one Mg2+, three La3+, and one Nb5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Mg2+, four La3+, and one Nb5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Mg2+, three La3+, and one Nb5+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two Ba2+, one Mg2+, two La3+, and one Nb5+ atom. In the sixth O2- site, O2- is bonded in a distorted linear geometry to one Ba2+, one Mg2+, three La3+, and one Nb5+ atom. In the seventh O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+, one Mg2+, one La3+, and one Nb5+ atom. In the eighth O2- site, O2- is bonded in a distorted linear geometry to two Ba2+, one Mg2+, two La3+, and one Nb5+ atom. In the ninth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+, one Mg2+, two equivalent La3+, and one Nb5+ atom. In the tenth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+, one Mg2+, two equivalent La3+, and one Nb5+ atom. In the eleventh O2- site, O2- is bonded in a distorted linear geometry to one Mg2+, four La3+, and one Nb5+ atom. In the twelfth O2- site, O2- is bonded in a 6-coordinate geometry to two Mg2+ and four La3+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted linear geometry to two Mg2+ and four La3+ atoms. In the fourteenth O2- site, O2- is bonded in a 6-coordinate geometry to two Mg2+ and four La3+ atoms.

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2020-05-02. Materials Data on Ba3La9Mg7Nb5O36 by Materials Project. https://doi.org/10.17188/1284811

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