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DOE OSTI · 1475664

Materials Data on Sr7CaFe6(CoO12)2 by Materials Project

Abstract

Sr7CaFe6(CoO12)2 is (Cubic) Perovskite-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are five inequivalent Sr sites. In the first Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two equivalent CaO12 cuboctahedra, faces with four SrO12 cuboctahedra, faces with two equivalent CoO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.73–2.77 Å. In the second Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, corners with eight equivalent SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two equivalent CoO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.75–2.79 Å. In the third Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, corners with eight SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two equivalent CoO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.73–2.80 Å. In the fourth Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two equivalent CoO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.73–2.77 Å. In the fifth Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two equivalent CaO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, faces with two equivalent CoO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.72–2.77 Å. Ca is bonded to twelve O atoms to form CaO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two equivalent CoO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.69–2.74 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six FeO6 octahedra, a faceface with one CaO12 cuboctahedra, and faces with seven SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There is three shorter (1.95 Å) and three longer (1.96 Å) Fe–O bond length. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with four FeO6 octahedra, a faceface with one CaO12 cuboctahedra, and faces with seven SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Fe–O bond distances ranging from 1.93–2.01 Å. Co is bonded to six O atoms to form CoO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with four equivalent FeO6 octahedra, a faceface with one CaO12 cuboctahedra, and faces with seven SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Co–O bond distances ranging from 1.89–1.96 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a distorted linear geometry to three Sr, one Ca, and two equivalent Fe atoms. In the second O site, O is bonded to three Sr, one Ca, and two equivalent Fe atoms to form distorted OSr3CaFe2 octahedra that share corners with fourteen OSr3CaFe2 octahedra, edges with two equivalent OSr3CaCo2 octahedra, and faces with four OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 1–61°. In the third O site, O is bonded to three Sr, one Ca, and two equivalent Co atoms to form distorted OSr3CaCo2 octahedra that share corners with ten OSr4Fe2 octahedra, edges with four equivalent OSr3CaFe2 octahedra, and faces with four equivalent OSr4FeCo octahedra. The corner-sharing octahedra tilt angles range from 1–60°. In the fourth O site, O is bonded to four Sr and two equivalent Fe atoms to form distorted OSr4Fe2 octahedra that share corners with twelve OSr4FeCo octahedra, edges with four equivalent OSr4Fe2 octahedra, and faces with four equivalent OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°. In the fifth O site, O is bonded to four Sr and two equivalent Fe atoms to form distorted OSr4Fe2 octahedra that share corners with fourteen OSr3CaFe2 octahedra, edges with four OSr4Fe2 octahedra, and faces with four OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 1–61°. In the sixth O site, O is bonded to four Sr and two equivalent Co atoms to form distorted OSr4Co2 octahedra that share corners with fourteen OSr4Fe2 octahedra, edges with four equivalent OSr4Fe2 octahedra, and faces with four equivalent OSr4FeCo octahedra. The corner-sharing octahedra tilt angles range from 0–60°. In the seventh O site, O is bonded to four Sr and two Fe atoms to form distorted OSr4Fe2 octahedra that share corners with sixteen OSr3CaFe2 octahedra, edges with four OSr4Fe2 octahedra, and faces with five OSr3CaFe2 octahedra. The corner-sharing octahedra tilt angles range from 1–61°. In the eighth O site, O is bonded to four Sr, one Fe, and one Co atom to form distorted OSr4FeCo octahedra that share corners with fourteen OSr3CaFe2 octahedra, edges with four OSr4Fe2 octahedra, and faces with six OSr3CaFe2 octahedra. The corner-sharing octahedra tilt angles range from 1–61°. In the ninth O site, O is bonded in a distorted linear geometry to three Sr, one Ca, and two Fe atoms. In the tenth O site, O is bonded in a distorted linear geometry to three Sr, one Ca, one Fe, and one Co atom.

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2020-08-03. Materials Data on Sr7CaFe6(CoO12)2 by Materials Project. https://doi.org/10.17188/1475664

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