Materials Data on Cr2FeNO8 by Materials Project

Abstract

(Cr2FeO8)2N2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional and consists of four ammonia molecules and one Cr2FeO8 framework. In the Cr2FeO8 framework, there are two inequivalent Cr4+ sites. In the first Cr4+ site, Cr4+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 29–41°. There are a spread of Cr–O bond distances ranging from 1.60–1.70 Å. In the second Cr4+ site, Cr4+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 19–35°. There are a spread of Cr–O bond distances ranging from 1.61–1.69 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six CrO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.03 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Cr4+ and one Fe3+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Cr4+ and one Fe3+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Cr4+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Cr4+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cr4+ and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cr4+ and one Fe3+ atom.