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DOE OSTI · 1717684

Materials Data on SrZn2Fe16O27 by Materials Project

Abstract

SrZn2Fe16O27 is beta indium sulfide-derived structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with six equivalent SrO12 cuboctahedra, edges with six equivalent FeO6 octahedra, edges with three equivalent FeO5 trigonal bipyramids, and faces with six equivalent FeO6 octahedra. There are six shorter (2.86 Å) and six longer (3.01 Å) Sr–O bond lengths. There are six inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO4 tetrahedra, corners with four equivalent ZnO4 tetrahedra, and edges with six FeO6 octahedra. There are four shorter (2.03 Å) and two longer (2.08 Å) Fe–O bond lengths. In the second Fe3+ site, Fe3+ is bonded to four O2- atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–60°. There is three shorter (1.93 Å) and one longer (1.99 Å) Fe–O bond length. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, a cornercorner with one ZnO4 tetrahedra, corners with two equivalent FeO4 tetrahedra, a cornercorner with one FeO5 trigonal bipyramid, an edgeedge with one SrO12 cuboctahedra, and edges with five FeO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Fe–O bond distances ranging from 1.96–2.17 Å. In the fourth Fe3+ site, Fe3+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with twelve FeO6 octahedra and edges with three equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 41–61°. There are three shorter (1.90 Å) and two longer (2.32 Å) Fe–O bond lengths. In the fifth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent FeO4 tetrahedra, corners with three equivalent ZnO4 tetrahedra, and edges with six FeO6 octahedra. There are three shorter (2.02 Å) and three longer (2.06 Å) Fe–O bond lengths. In the sixth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent FeO6 octahedra, corners with three equivalent FeO5 trigonal bipyramids, faces with three equivalent SrO12 cuboctahedra, and a faceface with one FeO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are three shorter (2.01 Å) and three longer (2.09 Å) Fe–O bond lengths. Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with twelve FeO6 octahedra. The corner-sharing octahedra tilt angles range from 56–61°. There is one shorter (1.96 Å) and three longer (2.02 Å) Zn–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Fe3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Fe3+ and one Zn2+ atom. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Fe3+ atoms. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Sr2+ and three Fe3+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Fe3+ and one Zn2+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+ and three Fe3+ atoms. In the seventh O2- site, O2- is bonded to four Fe3+ atoms to form distorted corner-sharing OFe4 tetrahedra.

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2020-04-29. Materials Data on SrZn2Fe16O27 by Materials Project. https://doi.org/10.17188/1717684

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