Materials Data on FeCo(PO4)2 by Materials Project

Abstract

FeCo(PO4)2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent CoO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Fe–O bond distances ranging from 1.95–2.16 Å. Co3+ is bonded to six O2- atoms to form distorted CoO6 octahedra that share corners with four equivalent FeO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Co–O bond distances ranging from 1.90–2.27 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 CoO6 octahedra, corners with three equivalent FeO6 octahedra, and an edgeedge with one CoO6 octahedra. The corner-sharing octahedra tilt angles range from 39–56°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one FeO6 octahedra, corners with three equivalent CoO6 octahedra, and an edgeedge with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–54°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. There are six 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 bent 120 degrees geometry to one Co3+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Fe3+, 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 distorted bent 120 degrees geometry to one Fe3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co3+ and one P5+ atom.