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Materials Data on Ca6V3Fe7O24 by Materials Project

Ca6V3Fe7O24 is Esseneite-like structured and crystallizes in the cubic I-43d space group. The structure is three-dimensional. Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.71 Å. V5+ is bonded to four equivalent O2- atoms to form VO4 tetrahedra that share corners with four equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 46°. All V–O bond lengths are 1.75 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent VO4 tetrahedra and corners with three equivalent FeO4 tetrahedra. There are three shorter (1.96 Å) and three longer (2.16 Å) Fe–O bond lengths. In the second Fe3+ site, Fe3+ is bonded to four equivalent O2- atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. All Fe–O bond lengths are 1.91 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one V5+, and one Fe3+ atom. In the second O2- site, O2- is bonded to two equivalent Ca2+ and two Fe3+ atoms to form a mixture of distorted edge and corner-sharing OCa2Fe2 trigonal pyramids.

36 MATERIALS SCIENCE↗