Materials Data on FeCo(PO4)2 by Materials Project

Abstract

FeCo(PO4)2 crystallizes in the trigonal R3 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 distorted FeO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one CoO6 octahedra. There are three shorter (1.93 Å) and three longer (2.11 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 CoO6 octahedra. There are three shorter (1.93 Å) and three longer (2.10 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 CoO6 octahedra. There are three shorter (1.92 Å) and three longer (2.10 Å) Fe–O bond lengths. There are three inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six O2- atoms to form distorted CoO6 octahedra that share corners with six PO4 tetrahedra, a faceface with one FeO6 octahedra, and a faceface with one CoO6 octahedra. There are three shorter (2.06 Å) and three longer (2.11 Å) Co–O bond lengths. In the second Co3+ site, Co3+ is bonded to six O2- atoms to form distorted CoO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one CoO6 octahedra. There are three shorter (1.90 Å) and three longer (2.10 Å) Co–O bond lengths. In the third Co3+ site, Co3+ is bonded to six O2- atoms to form distorted CoO6 octahedra that share corners with six PO4 tetrahedra and faces with two FeO6 octahedra. All Co–O bond lengths are 2.08 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 corners with three FeO6 octahedra and corners with three CoO6 octahedra. The corner-sharing octahedra tilt angles range from 30–53°. There are a spread of P–O bond distances ranging from 1.52–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra and corners with three CoO6 octahedra. The corner-sharing octahedra tilt angles range from 29–53°. There is two shorter (1.52 Å) and two longer (1.57 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 Fe3+, one Co3+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Co3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Fe3+, one Co3+, 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 two Co3+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Fe3+, one Co3+, 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.