Materials Data on FeP2O7 by Materials Project
FeP2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. 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 six PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.99–2.06 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.91–2.18 Å. There are four 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 and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of P–O bond distances ranging from 1.51–1.60 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 31–52°. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–56°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three FeO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–53°. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. There are fourteen inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one P atom. In the second O site, O is bonded in a bent 150 degrees geometry to two P atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two P atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the sixth O site, O is bonded in a single-bond geometry to one P atom. In the seventh O site, O is bonded in a single-bond geometry to one P atom. In the eighth O site, O is bonded in a single-bond geometry to one P atom. In the ninth O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom. In the tenth O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom. In the eleventh O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom. In the twelfth O site, O is bonded in a distorted trigonal planar geometry to two Fe and one P atom. In the thirteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one P atom. In the fourteenth O site, O is bonded in a distorted bent 150 degrees geometry to one Fe and one P atom.