Materials Data on BaYFe4O7 by Materials Project
YBaFe4O7.0 crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.75 Å) and four longer (3.17 Å) Ba–O bond lengths. Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with twelve equivalent FeO4 tetrahedra. All Y–O bond lengths are 2.30 Å. Fe+2.25+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three equivalent YO6 octahedra and corners with six equivalent FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–66°. There are a spread of Fe–O bond distances ranging from 1.97–2.05 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Y3+, and two equivalent Fe+2.25+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Y3+, and two equivalent Fe+2.25+ atoms. In the third O2- site, O2- is bonded in a tetrahedral geometry to four equivalent Fe+2.25+ atoms.