Materials Data on MnCr2Fe3(PO4)6 by Materials Project
Cr2MnFe3(PO4)6 crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are two inequivalent Cr+3.50+ sites. In the first Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form distorted CrO6 octahedra that share corners with six PO4 tetrahedra, a faceface with one MnO6 octahedra, and a faceface with one FeO6 octahedra. There are three shorter (2.08 Å) and three longer (2.09 Å) Cr–O bond lengths. In the second Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form distorted CrO6 octahedra that share corners with six PO4 tetrahedra and faces with two FeO6 octahedra. There are three shorter (2.08 Å) and three longer (2.09 Å) Cr–O bond lengths. Mn2+ is bonded to six O2- atoms to form distorted MnO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one CrO6 octahedra. There are three shorter (1.96 Å) and three longer (2.11 Å) Mn–O bond lengths. 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 CrO6 octahedra. There are three shorter (1.93 Å) and three longer (2.12 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 CrO6 octahedra. There are three shorter (1.93 Å) and three longer (2.12 Å) Fe–O bond lengths. In the third 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 CrO6 octahedra. There are three shorter (1.92 Å) and three longer (2.13 Å) Fe–O bond lengths. 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 MnO6 octahedra, corners with two CrO6 octahedra, and corners with three 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. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one MnO6 octahedra, corners with two CrO6 octahedra, and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 30–54°. There is two shorter (1.52 Å) and two longer (1.58 Å) P–O bond length. 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 Cr+3.50+, one Fe3+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Mn2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Cr+3.50+, one Fe3+, 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 Cr+3.50+, one Mn2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Cr+3.50+, one Fe3+, 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.