Materials Data on Ba2Fe3(P2O9)2 by Materials Project
Ba2Fe3(P2O9)2 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Ba is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Ba–O bond distances ranging from 2.65–3.18 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O 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 58°. There are a spread of Fe–O bond distances ranging from 2.02–2.06 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Fe–O bond distances ranging from 1.92–2.13 Å. There are two inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–50°. There is one shorter (1.52 Å) and three longer (1.56 Å) P–O bond length. In the second P site, P is bonded to four O 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 39–51°. There is two shorter (1.53 Å) and two longer (1.59 Å) P–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom. In the second O site, O is bonded in a 2-coordinate geometry to one Ba, one Fe, and one P atom. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Ba atoms. In the fourth O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom. In the fifth O site, O is bonded in a 2-coordinate geometry to one Ba, one Fe, and one P atom. In the sixth O site, O is bonded in a distorted single-bond geometry to two equivalent Ba and one P atom. In the seventh O site, O is bonded in a 2-coordinate geometry to one Ba, one Fe, and one P atom. In the eighth O site, O is bonded in a 2-coordinate geometry to one Ba, one Fe, and one P atom. In the ninth O site, O is bonded in a 2-coordinate geometry to one Ba, one Fe, and one P atom.