Materials Data on BaFe3(PO4)3 by Materials Project
BaFe3(PO4)3 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.76–2.81 Å. There are two inequivalent Fe+2.33+ sites. In the first Fe+2.33+ site, Fe+2.33+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent FeO6 octahedra and corners with six PO4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. There are four shorter (2.02 Å) and two longer (2.14 Å) Fe–O bond lengths. In the second Fe+2.33+ site, Fe+2.33+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. There are a spread of Fe–O bond distances ranging from 2.15–2.17 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 four FeO6 octahedra and an edgeedge with one FeO6 octahedra. The corner-sharing octahedra tilt angles range from 42–48°. There is two shorter (1.54 Å) and two longer (1.59 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 39–57°. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, one Fe+2.33+, and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Fe+2.33+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, one Fe+2.33+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, two equivalent Fe+2.33+, and one P5+ atom.