DOI: 10.17188/1475649
title: Materials Data on Sr7CaMnFe7O24 by Materials Project

description: Sr7CaMnFe7O24 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three 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 equivalent SrO12 cuboctahedra, a faceface with one MnO6 octahedra, and faces with seven FeO6 octahedra. There are one shorter (2.75 Å) and eleven longer (2.76 Å) Sr–O bond lengths. 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, a faceface with one MnO6 octahedra, and faces with seven FeO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.76–2.79 Å. In the third Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with twelve equivalent SrO12 cuboctahedra, faces with six equivalent SrO12 cuboctahedra, a faceface with one MnO6 octahedra, and faces with seven FeO6 octahedra. There are six shorter (2.76 Å) and six longer (2.77 Å) Sr–O bond lengths. Ca is bonded to twelve O atoms to form CaO12 cuboctahedra that share corners with twelve equivalent SrO12 cuboctahedra, faces with six equivalent SrO12 cuboctahedra, a faceface with one MnO6 octahedra, and faces with seven FeO6 octahedra. All Ca–O bond lengths are 2.74 Å. Mn is bonded to six O atoms to form MnO6 octahedra that share corners with six equivalent 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 (1.93 Å) and three longer (1.94 Å) Mn–O bond length. There are three 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 (1.94 Å) and three longer (1.95 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 MnO6 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 0–1°. There are a spread of Fe–O bond distances ranging from 1.96–1.98 Å. In the third Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six equivalent 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. There are six inequivalent O sites. In the first O site, O is bonded in a distorted linear geometry to three Sr, one Ca, and two Fe atoms. In the second O site, O is bonded in a distorted linear geometry to three Sr, one Ca, and two Fe atoms. In the third O site, O is bonded in a distorted linear geometry to three Sr, one Ca, one Mn, and one Fe atom. In the fourth O site, O is bonded to four Sr and two Fe atoms to form a mixture of distorted corner, edge, and face-sharing OSr4Fe2 octahedra. The corner-sharing octahedral tilt angles are 60°. In the fifth O site, O is bonded to four Sr and two Fe atoms to form a mixture of distorted corner, edge, and face-sharing OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°. In the sixth O site, O is bonded in a distorted linear geometry to four Sr, one Mn, and one Fe atom.