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DOE OSTI · 1749277

Materials Data on Sr14Nb6O29 by Materials Project

Abstract

Sr14Nb6O29 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are fourteen inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–3.14 Å. In the second Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.49–2.68 Å. In the third Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 square pyramids that share a cornercorner with one SrO6 octahedra, corners with three equivalent NbO6 octahedra, a cornercorner with one NbO5 trigonal bipyramid, and an edgeedge with one NbO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 18–39°. There are a spread of Sr–O bond distances ranging from 2.39–3.22 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.44–2.84 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.71 Å. In the sixth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with three equivalent NbO6 octahedra and corners with three equivalent NbO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 16–39°. There are a spread of Sr–O bond distances ranging from 2.44–2.70 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–2.75 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.49–2.65 Å. In the ninth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.57–3.06 Å. In the tenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with three equivalent NbO6 octahedra and corners with three equivalent NbO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 21–29°. There are a spread of Sr–O bond distances ranging from 2.43–2.64 Å. In the eleventh Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.37–2.53 Å. In the twelfth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.86 Å. In the thirteenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with three equivalent NbO6 octahedra, a cornercorner with one SrO6 square pyramid, and corners with three equivalent NbO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 22–28°. There are a spread of Sr–O bond distances ranging from 2.41–2.71 Å. In the fourteenth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.54–2.78 Å. There are six inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to five O2- atoms to form distorted NbO5 trigonal bipyramids that share corners with three equivalent SrO6 octahedra, a cornercorner with one SrO6 square pyramid, and an edgeedge with one SrO6 square pyramid. The corner-sharing octahedra tilt angles range from 44–59°. There are a spread of Nb–O bond distances ranging from 1.91–2.01 Å. In the second Nb5+ site, Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.84–2.20 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with three equivalent SrO6 octahedra and corners with three equivalent SrO6 square pyramids. The corner-sharing octahedra tilt angles range from 16–39°. There are a spread of Nb–O bond distances ranging from 2.00–2.11 Å. In the fourth Nb5+ site, Nb5+ is bonded to five O2- atoms to form distorted NbO5 trigonal bipyramids that share corners with three equivalent SrO6 octahedra. The corner-sharing octahedra tilt angles range from 52–56°. There are a spread of Nb–O bond distances ranging from 1.88–2.04 Å. In the fifth Nb5+ site, Nb5+ is bonded to five O2- atoms to form distorted NbO5 trigonal bipyramids that share corners with three equivalent SrO6 octahedra. The corner-sharing octahedra tilt angles range from 47–54°. There are a spread of Nb–O bond distances ranging from 1.89–2.12 Å. In the sixth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six SrO6 octahedra. The corner-sharing octahedra tilt angles range from 21–29°. There are a spread of Nb–O bond distances ranging from 2.00–2.09 Å. There are twenty-nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Nb5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Nb5+ atom. In the third O2- site, O2- is bonded to four Sr2+ and one Nb5+ atom to form distorted OSr4Nb square pyramids that share a cornercorner with one OSr4Nb square pyramid, a cornercorner with one OSr3Nb tetrahedra, an edgeedge with one OSr4Nb square pyramid, and an edgeedge with one OSr3Nb tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Nb5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Nb5+ atom. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Sr2+ and one Nb5+ atom. In the seventh O2- site, O2- is bonded to four Sr2+ and one Nb5+ atom to form distorted OSr4Nb square pyramids that share a cornercorner with one OSr4Nb square pyramid, corners with four OSr3Nb tetrahedra, an edgeedge with one OSr4Nb square pyramid, and an edgeedge with one OSr3Nb tetrahedra. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and one Nb5+ atom. In the ninth O2- site, O2- is bonded to three Sr2+ and one Nb5+ atom to form distorted OSr3Nb tetrahedra that share corners with two equivalent OSr4Nb square pyramids and corners with two OSr2Nb2 tetrahedra. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Nb5+ atom. In the eleventh O2- site, O2- is bonded to three Sr2+ and one Nb5+ atom to form distorted OSr3Nb tetrahedra that share corners with three OSr4Nb square pyramids, a cornercorner with one OSr3Nb tetrahedra, and edges with two OSr4Nb square pyramids. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Nb5+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Nb5+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Nb5+ atom. In the fifteenth O2- site, O2- is bonded to two Sr2+ and two Nb5+ atoms to form a mixture of distorted edge and corner-sharing OSr2Nb2 tetrahedra. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Nb5+ atoms. In the seventeenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Sr2+ and two Nb5+ atoms. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Nb5+ atoms. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Nb5+ atom. In the twentieth O2- site, O2- is bonded to four Sr2+ and one Nb5+ atom to form distorted OSr4Nb square pyramids that share corners with two equivalent OSr3Nb tetrahedra, a cornercorner with one OSr4Nb trigonal bipyramid, and edges with two equivalent OSr4Nb trigonal bipyramids. In the twenty-first O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Nb5+ atom. In the twenty-second O2- site, O2- is bonded to three Sr2+ and one Nb5+ atom to form distorted OSr3Nb tetrahedra that share corners with two equivalent OSr4Nb square pyramids, corners with two equivalent OSr4Nb trigonal bipyramids, and an edgeedge with one OSr2Nb2 tetrahedra. In the twenty-third O2- site, O2- is bonded to four Sr2+ and one Nb5+ atom to form distorted OSr4Nb trigonal bipyramids that share a cornercorner with one OSr4Nb square pyramid, corners with two equivalent OSr3Nb tetrahedra, and edges with two equivalent OSr4Nb square pyramids. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Nb5+ atom. In the twenty-fifth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Nb5+ atom. In the twenty-sixth O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+ and one Nb5+ atom. In the twenty-seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Nb5+ atom. In the twenty-eighth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Nb5+ atom. In the twenty-ninth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Nb5+ atom.

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2020-04-30. Materials Data on Sr14Nb6O29 by Materials Project. https://doi.org/10.17188/1749277

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