DOI: 10.17188/1308814
title: Materials Data on CrFe3Ni2(PO4)6 by Materials Project

description: CrFe3Ni2(PO4)6 crystallizes in the trigonal R3 space group. The structure is three-dimensional. Cr5+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one NiO6 octahedra. There is three shorter (1.90 Å) and three longer (1.99 Å) Cr–O bond length. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one NiO6 octahedra. There are three shorter (1.94 Å) and three longer (2.07 Å) Fe–O bond lengths. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one NiO6 octahedra. There are three shorter (1.95 Å) and three longer (2.11 Å) Fe–O bond lengths. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one NiO6 octahedra. There are three shorter (1.93 Å) and three longer (2.08 Å) Fe–O bond lengths. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to six O2- atoms to form distorted NiO6 octahedra that share corners with six PO4 tetrahedra, a faceface with one CrO6 octahedra, and a faceface with one FeO6 octahedra. There are three shorter (2.14 Å) and three longer (2.17 Å) Ni–O bond lengths. In the second Ni2+ site, Ni2+ is bonded to six O2- atoms to form distorted NiO6 octahedra that share corners with six PO4 tetrahedra and faces with two FeO6 octahedra. All Ni–O bond lengths are 2.13 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one CrO6 octahedra, corners with two NiO6 octahedra, and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 26–53°. There is one shorter (1.52 Å) and three longer (1.56 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one CrO6 octahedra, corners with two NiO6 octahedra, and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 29–51°. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. There are eight 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 Fe3+, one Ni2+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Cr5+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Fe3+, one Ni2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Cr5+, one Ni2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Fe3+, one Ni2+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom.