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DOE OSTI · 1318860

Materials Data on Ca(Fe9O13)2 by Materials Project

Abstract

Ca(Fe9O13)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.31–2.44 Å. There are eighteen inequivalent Fe+2.78+ sites. In the first Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 10–15°. There are a spread of Fe–O bond distances ranging from 2.01–2.15 Å. In the second Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 10–16°. There are a spread of Fe–O bond distances ranging from 2.13–2.20 Å. In the third Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 6–17°. There are a spread of Fe–O bond distances ranging from 2.00–2.23 Å. In the fourth Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 7–16°. There are a spread of Fe–O bond distances ranging from 1.94–2.19 Å. In the fifth Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are a spread of Fe–O bond distances ranging from 1.90–2.17 Å. In the sixth Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are a spread of Fe–O bond distances ranging from 1.91–2.20 Å. In the seventh Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 14–16°. There are a spread of Fe–O bond distances ranging from 2.01–2.23 Å. In the eighth Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 13–15°. There are a spread of Fe–O bond distances ranging from 1.99–2.30 Å. In the ninth Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 10–11°. There are a spread of Fe–O bond distances ranging from 1.92–2.14 Å. In the tenth Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 10–11°. There are a spread of Fe–O bond distances ranging from 1.90–2.20 Å. In the eleventh Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 12–16°. There are a spread of Fe–O bond distances ranging from 1.90–2.30 Å. In the twelfth Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 13–17°. There are a spread of Fe–O bond distances ranging from 1.89–2.34 Å. In the thirteenth Fe+2.78+ site, Fe+2.78+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 1.82–2.60 Å. In the fourteenth Fe+2.78+ site, Fe+2.78+ is bonded in a 3-coordinate geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 1.81–2.62 Å. In the fifteenth Fe+2.78+ site, Fe+2.78+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Fe–O bond distances ranging from 1.90–2.09 Å. In the sixteenth Fe+2.78+ site, Fe+2.78+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Fe–O bond distances ranging from 1.88–2.22 Å. In the seventeenth Fe+2.78+ site, Fe+2.78+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Fe–O bond distances ranging from 1.83–2.31 Å. In the eighteenth Fe+2.78+ site, Fe+2.78+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Fe–O bond distances ranging from 1.84–2.28 Å. There are twenty-six inequivalent O2- sites. In the first O2- site, O2- is bonded to six Fe+2.78+ atoms to form distorted OFe6 octahedra that share corners with four OFe5 square pyramids, edges with two equivalent OFe6 octahedra, edges with six OFe5 square pyramids, and edges with two OCaFe3 tetrahedra. In the second O2- site, O2- is bonded to six Fe+2.78+ atoms to form distorted OFe6 octahedra that share corners with four OFe5 square pyramids, edges with two equivalent OFe6 octahedra, edges with six OFe5 square pyramids, and edges with two OCaFe3 tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ca2+ and two Fe+2.78+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ca2+ and two Fe+2.78+ atoms. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two Fe+2.78+ atoms. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to two Fe+2.78+ atoms. In the seventh O2- site, O2- is bonded to five Fe+2.78+ atoms to form OFe5 square pyramids that share corners with two equivalent OFe6 octahedra, corners with four OCaFe3 tetrahedra, edges with three OFe6 octahedra, edges with four OFe5 square pyramids, and an edgeedge with one OCaFe3 tetrahedra. The corner-sharing octahedra tilt angles range from 5–6°. In the eighth O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 square pyramids that share corners with two equivalent OFe6 octahedra, corners with four OCaFe3 tetrahedra, edges with three OFe6 octahedra, edges with four OFe5 square pyramids, and an edgeedge with one OCaFe3 tetrahedra. The corner-sharing octahedra tilt angles range from 3–4°. In the ninth O2- site, O2- is bonded to five Fe+2.78+ atoms to form OFe5 square pyramids that share corners with two equivalent OFe6 octahedra, a cornercorner with one OCaFe3 tetrahedra, edges with three OFe6 octahedra, and edges with four OFe5 square pyramids. The corner-sharing octahedra tilt angles range from 10–12°. In the tenth O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 square pyramids that share corners with two equivalent OFe6 octahedra, a cornercorner with one OCaFe3 tetrahedra, edges with three OFe6 octahedra, and edges with four OFe5 square pyramids. The corner-sharing octahedra tilt angles range from 11–13°. In the eleventh O2- site, O2- is bonded to one Ca2+ and three Fe+2.78+ atoms to form distorted OCaFe3 tetrahedra that share corners with five OFe5 square pyramids, corners with three OCaFe3 tetrahedra, edges with two OFe6 octahedra, an edgeedge with one OFe5 square pyramid, and an edgeedge with one OCaFe3 tetrahedra. In the twelfth O2- site, O2- is bonded to one Ca2+ and three Fe+2.78+ atoms to form distorted OCaFe3 tetrahedra that share corners with five OFe5 square pyramids, corners with three OCaFe3 tetrahedra, edges with two OFe6 octahedra, an edgeedge with one OFe5 square pyramid, and an edgeedge with one OCaFe3 tetrahedra. In the thirteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Fe+2.78+ atoms. In the fourteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Fe+2.78+ atoms. In the fifteenth O2- site, O2- is bonded to one Ca2+ and three Fe+2.78+ atoms to form distorted OCaFe3 tetrahedra that share corners with six OFe5 square pyramids, corners with three OCaFe3 tetrahedra, a cornercorner with one OFe5 trigonal bipyramid, an edgeedge with one OCaFe3 tetrahedra, and an edgeedge with one OFe5 trigonal bipyramid. In the sixteenth O2- site, O2- is bonded to one Ca2+ and three Fe+2.78+ atoms to form OCaFe3 tetrahedra that share corners with four OFe5 square pyramids, corners with three OCaFe3 tetrahedra, corners with three equivalent OFe5 trigonal bipyramids, an edgeedge with one OFe5 square pyramid, and an edgeedge with one OCaFe3 tetrahedra. In the seventeenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Fe+2.78+ atoms. In the eighteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Fe+2.78+ atoms. In the nineteenth O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 trigonal bipyramids that share corners with five OFe5 square pyramids, corners with four OCaFe3 tetrahedra, edges with five OFe5 square pyramids, and an edgeedge with one OCaFe3 tetrahedra. In the twentieth O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 square pyramids that share corners with five OFe5 square pyramids, corners with four OCaFe3 tetrahedra, edges with three OFe5 square pyramids, an edgeedge with one OCaFe3 tetrahedra, and edges with two equivalent OFe5 trigonal bipyramids. In the twenty-first O2- site, O2- is bonded to five Fe+2.78+ atoms to form a mixture of distorted edge and corner-sharing OFe5 square pyramids. In the twenty-second O2- site, O2- is bonded to five Fe+2.78+ atoms to form a mixture of edge and corner-sharing OFe5 square pyramids. In the twenty-third O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 square pyramids that share corners with five OFe5 square pyramids, corners with two OCaFe3 tetrahedra, a cornercorner with one OFe5 trigonal bipyramid, edges with seven OFe5 square pyramids, and an edgeedge with one OFe5 trigonal bipyramid. In the twenty-fourth O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 square pyramids that share corners with three OFe5 square pyramids, corners with two OCaFe3 tetrahedra, corners with three equivalent OFe5 trigonal bipyramids, and edges with eight OFe5 square pyramids. In the twenty-fifth O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 square pyramids that share corners with six OFe5 square pyramids, a cornercorner with one OCaFe3 tetrahedra, edges with seven OFe5 square pyramids, and an edgeedge with one OFe5 trigonal bipyramid. In the twenty-sixth O2- site, O2- is bonded to five Fe+2.78+ atoms to form distorted OFe5 square pyramids that share corners with six OFe5 square pyramids, a cornercorner with one OCaFe3 tetrahedra, edges with seven OFe5 square pyramids, and an edgeedge with one OFe5 trigonal bipyramid.

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2020-08-03. Materials Data on Ca(Fe9O13)2 by Materials Project. https://doi.org/10.17188/1318860

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