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DOE OSTI · 1207837

Materials Data on Ba3Na2Ti3Nb2O15 by Materials Project

Abstract

Na2Ba3Ti3Nb2O15 is (Cubic) Perovskite-derived structured and crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with six equivalent NaO12 cuboctahedra, corners with six BaO12 cuboctahedra, faces with two equivalent BaO12 cuboctahedra, faces with four equivalent NaO12 cuboctahedra, faces with two equivalent TiO6 octahedra, and faces with six equivalent NbO6 octahedra. There are a spread of Na–O bond distances ranging from 2.79–2.87 Å. 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 five equivalent NaO12 cuboctahedra, corners with seven BaO12 cuboctahedra, faces with two equivalent NaO12 cuboctahedra, faces with four BaO12 cuboctahedra, faces with two equivalent NbO6 octahedra, and faces with six TiO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.82–2.89 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with two equivalent NaO12 cuboctahedra, corners with ten BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.84–2.87 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with eight BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ti–O bond lengths are 2.01 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four TiO6 octahedra, faces with two equivalent NaO12 cuboctahedra, and faces with six BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Ti–O bond distances ranging from 1.99–2.03 Å. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four equivalent NbO6 octahedra, faces with two equivalent BaO12 cuboctahedra, and faces with six equivalent NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Nb–O bond distances ranging from 2.00–2.02 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to three equivalent Na1+, one Ba2+, and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Ti4+ atoms. There are two shorter (2.82 Å) and two longer (2.84 Å) O–Ba bond lengths. Both O–Ti bond lengths are 2.01 Å. In the third O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two Ti4+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+, two equivalent Ba2+, one Ti4+, and one Nb5+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Na1+ and two equivalent Nb5+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Ti4+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to one Na1+, three Ba2+, and two equivalent Ti4+ atoms.

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2020-05-02. Materials Data on Ba3Na2Ti3Nb2O15 by Materials Project. https://doi.org/10.17188/1207837

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