Materials Data on Fe4Bi2O9 by Materials Project

Abstract

Bi2Fe4O9 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four FeO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.07 Å. In the second Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four equivalent FeO6 octahedra and a cornercorner with one FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–58°. There are a spread of Fe–O bond distances ranging from 1.86–1.94 Å. In the third Fe3+ site, Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four equivalent FeO6 octahedra and a cornercorner with one FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Fe–O bond distances ranging from 1.87–1.93 Å. Bi3+ is bonded in a 4-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.15–3.07 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three Fe3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Fe3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and two equivalent Bi3+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe3+ and two equivalent Bi3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Fe3+ and two equivalent Bi3+ atoms. In the sixth O2- site, O2- is bonded in a linear geometry to two Fe3+ atoms.