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DOE OSTI · 1318857

Materials Data on Sr9Zn2(CuO7)2 by Materials Project

Abstract

Sr9Zn2(CuO7)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are nine inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with three SrO6 octahedra, edges with seven SrO6 octahedra, and edges with two equivalent ZnO4 tetrahedra. The corner-sharing octahedra tilt angles range from 3–55°. There are a spread of Sr–O bond distances ranging from 2.50–2.65 Å. In the second 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 2.56–2.95 Å. In the third Sr2+ site, Sr2+ is bonded to six O2- atoms to form a mixture of distorted corner and edge-sharing SrO6 octahedra. The corner-sharing octahedra tilt angles range from 3–60°. There are a spread of Sr–O bond distances ranging from 2.43–2.82 Å. In the fourth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with two equivalent SrO6 octahedra, a cornercorner with one ZnO4 tetrahedra, edges with five SrO6 octahedra, and edges with two equivalent ZnO4 tetrahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of Sr–O bond distances ranging from 2.41–2.78 Å. In the fifth 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 2.45–3.10 Å. In the sixth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with four SrO6 octahedra, corners with two equivalent ZnO4 tetrahedra, edges with two equivalent SrO6 octahedra, and a faceface with one SrO6 octahedra. The corner-sharing octahedra tilt angles range from 35–63°. There are a spread of Sr–O bond distances ranging from 2.45–2.61 Å. In the seventh Sr2+ site, Sr2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing SrO6 octahedra. The corner-sharing octahedra tilt angles range from 2–63°. There are a spread of Sr–O bond distances ranging from 2.42–2.74 Å. In the eighth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 octahedra that share corners with four SrO6 octahedra, corners with two equivalent ZnO4 tetrahedra, edges with two equivalent SrO6 octahedra, and a faceface with one SrO6 octahedra. The corner-sharing octahedra tilt angles range from 21–60°. There are a spread of Sr–O bond distances ranging from 2.46–2.68 Å. In the ninth Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.58–2.89 Å. There are two inequivalent Cu3+ sites. In the first Cu3+ site, Cu3+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.78 Å) and one longer (1.81 Å) Cu–O bond length. In the second Cu3+ site, Cu3+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.78 Å) and one longer (1.81 Å) Cu–O bond length. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent SrO6 octahedra, corners with two equivalent ZnO4 tetrahedra, and edges with two equivalent SrO6 octahedra. The corner-sharing octahedral tilt angles are 71°. There are a spread of Zn–O bond distances ranging from 1.93–2.03 Å. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with three SrO6 octahedra, corners with two equivalent ZnO4 tetrahedra, and edges with two equivalent SrO6 octahedra. The corner-sharing octahedra tilt angles range from 8–70°. There are a spread of Zn–O bond distances ranging from 1.94–2.02 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to five Sr2+ and one Zn2+ atom. In the second O2- site, O2- is bonded to five Sr2+ and one Zn2+ atom to form distorted OSr5Zn octahedra that share corners with two equivalent OSr5Cu octahedra, corners with four OSr4Zn square pyramids, edges with three OSr5Zn octahedra, an edgeedge with one OSr5 square pyramid, edges with two equivalent OSr5 trigonal bipyramids, and edges with two equivalent OSr2Zn2 trigonal pyramids. The corner-sharing octahedral tilt angles are 7°. In the third O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Cu3+ atom. In the fourth O2- site, O2- is bonded to four Sr2+ and one Zn2+ atom to form distorted OSr4Zn square pyramids that share corners with two equivalent OSr5Zn octahedra, corners with two equivalent OSr5 trigonal bipyramids, corners with two equivalent OSr2Zn2 trigonal pyramids, edges with two equivalent OSr4Zn square pyramids, and an edgeedge with one OSr5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 44°. In the fifth O2- site, O2- is bonded to five Sr2+ and one Cu3+ atom to form distorted OSr5Cu octahedra that share corners with two equivalent OSr5Zn octahedra, corners with two equivalent OSr5 square pyramids, corners with two equivalent OSr2Zn2 trigonal pyramids, edges with five OSr5Zn octahedra, and an edgeedge with one OSr5 square pyramid. The corner-sharing octahedral tilt angles are 7°. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two equivalent Zn2+ atoms. In the seventh O2- site, O2- is bonded to five Sr2+ atoms to form distorted OSr5 trigonal bipyramids that share corners with two equivalent OSr5Cu octahedra, corners with two equivalent OSr4Zn square pyramids, edges with three OSr5Zn octahedra, edges with three OSr4Zn square pyramids, and edges with two equivalent OSr5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 16°. In the eighth O2- site, O2- is bonded to five Sr2+ atoms to form distorted OSr5 square pyramids that share corners with four OSr5Cu octahedra, edges with four OSr5Zn octahedra, edges with two equivalent OSr5 square pyramids, and edges with two equivalent OSr5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 10–24°. In the ninth O2- site, O2- is bonded to two Sr2+ and two equivalent Zn2+ atoms to form distorted OSr2Zn2 trigonal pyramids that share corners with two equivalent OSr5Cu octahedra, corners with two equivalent OSr4Zn square pyramids, corners with two equivalent OSr2Zn2 trigonal pyramids, and edges with two equivalent OSr5Zn octahedra. The corner-sharing octahedra tilt angles range from 74–75°. In the tenth O2- site, O2- is bonded to five Sr2+ and one Cu3+ atom to form distorted OSr5Cu octahedra that share corners with two equivalent OSr5 trigonal bipyramids, edges with four OSr5Cu octahedra, edges with two equivalent OSr5 square pyramids, and an edgeedge with one OSr5 trigonal bipyramid. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Cu3+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to three Sr2+ atoms. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Zn2+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ atoms.

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2020-05-02. Materials Data on Sr9Zn2(CuO7)2 by Materials Project. https://doi.org/10.17188/1318857

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