Materials Data on BaLuFe4O7 by Materials Project

Abstract

BaLuFe4O7 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 (2.82 Å) and four longer (3.21 Å) Ba–O bond lengths. Lu3+ is bonded to six O2- atoms to form LuO6 octahedra that share corners with twelve equivalent FeO4 tetrahedra. There are two shorter (2.22 Å) and four longer (2.24 Å) Lu–O bond lengths. Fe+2.25+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with three equivalent LuO6 octahedra and corners with six equivalent FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–60°. There are a spread of Fe–O bond distances ranging from 1.96–2.05 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Lu3+, and two equivalent Fe+2.25+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+, one Lu3+, 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.