Materials Data on AlFe2BO5 by Materials Project

Abstract

Fe2AlBO5 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are three inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with two equivalent AlO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 60–70°. There are a spread of Fe–O bond distances ranging from 2.02–2.22 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, edges with two equivalent FeO6 octahedra, and edges with four equivalent AlO6 octahedra. The corner-sharing octahedral tilt angles are 70°. There are two shorter (2.08 Å) and four longer (2.22 Å) Fe–O bond lengths. In the third Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent AlO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with six FeO6 octahedra. The corner-sharing octahedral tilt angles are 17°. There are two shorter (2.05 Å) and four longer (2.21 Å) Fe–O bond lengths. Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with four FeO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with five FeO6 octahedra. The corner-sharing octahedra tilt angles range from 17–60°. There are a spread of Al–O bond distances ranging from 1.93–2.05 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.40 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Fe2+, one Al3+, and one B3+ atom. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Fe2+, one Al3+, and one B3+ atom. In the third O2- site, O2- is bonded to two Fe2+ and two equivalent Al3+ atoms to form OAl2Fe2 tetrahedra that share corners with three equivalent OAl2Fe3 square pyramids, corners with three equivalent OAl2Fe2 tetrahedra, and an edgeedge with one OAl2Fe3 square pyramid. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Fe2+ and one B3+ atom. In the fifth O2- site, O2- is bonded to three Fe2+ and two equivalent Al3+ atoms to form OAl2Fe3 square pyramids that share corners with two equivalent OAl2Fe3 square pyramids, corners with three equivalent OAl2Fe2 tetrahedra, edges with three equivalent OAl2Fe3 square pyramids, and an edgeedge with one OAl2Fe2 tetrahedra.