Materials Data on CrFe2(PO4)3 by Materials Project
CrFe2(PO4)3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Cr3+ is bonded to six equivalent O2- atoms to form distorted CrO6 octahedra that share corners with six equivalent PO4 tetrahedra and faces with two equivalent FeO6 octahedra. All Cr–O bond lengths are 2.08 Å. Fe3+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six equivalent PO4 tetrahedra and a faceface with one CrO6 octahedra. There are three shorter (1.93 Å) and three longer (2.11 Å) Fe–O bond lengths. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent CrO6 octahedra and corners with four equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 30–54°. There is two shorter (1.52 Å) and two longer (1.57 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Fe3+, and one P5+ atom.