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DOE OSTI · 1475714

Materials Data on SrCa7FeCo7O24 by Materials Project

Abstract

SrCa7FeCo7O24 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with twelve equivalent CaO12 cuboctahedra, faces with six equivalent CaO12 cuboctahedra, a faceface with one FeO6 octahedra, and faces with seven CoO6 octahedra. There are nine shorter (2.71 Å) and three longer (2.72 Å) Sr–O bond lengths. There are three inequivalent Ca sites. In the first Ca site, Ca is bonded to twelve O atoms to form CaO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, corners with eight equivalent CaO12 cuboctahedra, faces with six CaO12 cuboctahedra, a faceface with one FeO6 octahedra, and faces with seven CoO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.63–2.71 Å. In the second Ca site, Ca is bonded to twelve O atoms to form CaO12 cuboctahedra that share corners with twelve CaO12 cuboctahedra, faces with two equivalent SrO12 cuboctahedra, faces with four equivalent CaO12 cuboctahedra, a faceface with one FeO6 octahedra, and faces with seven CoO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.66–2.71 Å. In the third Ca site, Ca is bonded to twelve O atoms to form CaO12 cuboctahedra that share corners with twelve equivalent CaO12 cuboctahedra, faces with six equivalent CaO12 cuboctahedra, a faceface with one FeO6 octahedra, and faces with seven CoO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.65–2.69 Å. Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six equivalent CoO6 octahedra, a faceface with one SrO12 cuboctahedra, and faces with seven CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. All Fe–O bond lengths are 1.93 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded to six O atoms to form CoO6 octahedra that share corners with six equivalent CoO6 octahedra, a faceface with one SrO12 cuboctahedra, and faces with seven CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There is three shorter (1.87 Å) and three longer (1.89 Å) Co–O bond length. In the second Co site, Co is bonded to six O atoms to form CoO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four equivalent CoO6 octahedra, a faceface with one SrO12 cuboctahedra, and faces with seven CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Co–O bond distances ranging from 1.86–1.88 Å. In the third Co site, Co is bonded to six O atoms to form CoO6 octahedra that share corners with six CoO6 octahedra, a faceface with one SrO12 cuboctahedra, and faces with seven CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Co–O bond distances ranging from 1.90–1.93 Å. There are six inequivalent O sites. In the first O site, O is bonded to four Ca, one Fe, and one Co atom to form distorted OCa4FeCo octahedra that share corners with ten OSrCa3FeCo octahedra and faces with six OCa4FeCo octahedra. The corner-sharing octahedra tilt angles range from 1–60°. In the second O site, O is bonded in a distorted linear geometry to four Ca and two Co atoms. In the third O site, O is bonded in a distorted linear geometry to four Ca and two Co atoms. In the fourth O site, O is bonded to one Sr, three Ca, one Fe, and one Co atom to form distorted OSrCa3FeCo octahedra that share corners with fourteen OCa4FeCo octahedra, edges with four equivalent OSrCa3Co2 octahedra, and faces with six OCa4FeCo octahedra. The corner-sharing octahedra tilt angles range from 1–61°. In the fifth O site, O is bonded to one Sr, three Ca, and two Co atoms to form distorted OSrCa3Co2 octahedra that share corners with fourteen OCa4FeCo octahedra, edges with four OSrCa3FeCo octahedra, and faces with five OCa4FeCo octahedra. The corner-sharing octahedra tilt angles range from 1–61°. In the sixth O site, O is bonded to one Sr, three Ca, and two Co atoms to form distorted OSrCa3Co2 octahedra that share corners with sixteen OCa4FeCo octahedra, edges with four equivalent OSrCa3Co2 octahedra, and faces with four OSrCa3Co2 octahedra. The corner-sharing octahedra tilt angles range from 1–61°.

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2020-07-15. Materials Data on SrCa7FeCo7O24 by Materials Project. https://doi.org/10.17188/1475714

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