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DOE OSTI · 1676929

Materials Data on Ba2SmNb4FeO15 by Materials Project

Abstract

Ba2SmNb4FeO15 is Pb (Zr_0.50 Ti_0.48) O_3-derived structured and crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Ba–O bond distances ranging from 2.76–3.39 Å. In the second Ba2+ site, Ba2+ is bonded in a 3-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.74–3.27 Å. Sm3+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Sm–O bond distances ranging from 2.27–3.08 Å. There are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one FeO6 octahedra and corners with five NbO6 octahedra. The corner-sharing octahedra tilt angles range from 4–43°. There are a spread of Nb–O bond distances ranging from 1.86–2.22 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with two equivalent FeO6 octahedra and corners with four NbO6 octahedra. The corner-sharing octahedra tilt angles range from 14–43°. There are a spread of Nb–O bond distances ranging from 1.91–2.20 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one FeO6 octahedra and corners with five NbO6 octahedra. The corner-sharing octahedra tilt angles range from 8–38°. There are a spread of Nb–O bond distances ranging from 1.89–2.20 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 9–38°. There are a spread of Nb–O bond distances ranging from 1.87–2.21 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra and corners with four NbO6 octahedra. The corner-sharing octahedra tilt angles range from 9–41°. There are a spread of Fe–O bond distances ranging from 1.97–2.10 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+ and two Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Ba2+ and two Nb5+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, two equivalent Sm3+, one Nb5+, and one Fe3+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Ba2+, one Sm3+, and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Ba2+, one Nb5+, and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Ba2+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+ and two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, one Nb5+, and one Fe3+ atom. In the ninth O2- site, O2- is bonded in a distorted linear geometry to one Ba2+, one Sm3+, and two equivalent Nb5+ atoms. In the tenth O2- site, O2- is bonded in a distorted T-shaped geometry to two Ba2+, one Sm3+, and two equivalent Fe3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted linear geometry to two Ba2+ and two equivalent Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sm3+, one Nb5+, and one Fe3+ atom. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sm3+ and two Nb5+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Sm3+, and two equivalent Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Sm3+, and two equivalent Nb5+ atoms.

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2020-04-30. Materials Data on Ba2SmNb4FeO15 by Materials Project. https://doi.org/10.17188/1676929

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