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DOE OSTI · 1662568

Materials Data on Sr3TiNb4O15 by Materials Project

Abstract

Sr3TiNb4O15 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share faces with two equivalent SrO12 cuboctahedra, faces with two equivalent TiO6 octahedra, and faces with six NbO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.65–2.94 Å. In the second Sr2+ site, Sr2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.67–3.12 Å. In the third Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.57–3.13 Å. Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four NbO6 octahedra, and faces with two equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 10–43°. There are a spread of Ti–O bond distances ranging from 1.80–2.22 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 corners with six NbO6 octahedra and faces with two equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 5–44°. There are a spread of Nb–O bond distances ranging from 1.92–2.13 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with five NbO6 octahedra, and faces with two equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 13–44°. There are a spread of Nb–O bond distances ranging from 1.93–2.15 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four NbO6 octahedra, and faces with two equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 5–43°. There are a spread of Nb–O bond distances ranging from 1.94–2.08 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one TiO6 octahedra and corners with five NbO6 octahedra. The corner-sharing octahedra tilt angles range from 5–43°. There are a spread of Nb–O bond distances ranging from 1.87–2.15 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+, one Ti4+, and one Nb5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two equivalent Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two equivalent Nb5+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+, one Ti4+, and one Nb5+ atom. In the tenth O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, one Ti4+, and one Nb5+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+, one Ti4+, and one Nb5+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted linear geometry to two Sr2+ and two equivalent Nb5+ atoms.

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2020-07-15. Materials Data on Sr3TiNb4O15 by Materials Project. https://doi.org/10.17188/1662568

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