Materials Data on BaFe2(PO4)2 by Materials Project

Abstract

BaFe2(PO4)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent FeO6 octahedra, edges with six equivalent BaO12 cuboctahedra, edges with six equivalent PO4 tetrahedra, and faces with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are a spread of Ba–O bond distances ranging from 2.91–3.38 Å. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent BaO12 cuboctahedra, corners with six equivalent PO4 tetrahedra, edges with three equivalent FeO6 octahedra, and a faceface with one BaO12 cuboctahedra. There are a spread of Fe–O bond distances ranging from 2.11–2.22 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with six equivalent FeO6 octahedra and edges with three equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 47–55°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, two equivalent Fe2+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Ba2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, two equivalent Fe2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, two equivalent Fe2+, and one P5+ atom.