Materials Data on LiFe2P2O9 by Materials Project

Abstract

LiFe2P2O9 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Li–O bond distances ranging from 2.03–2.37 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 two equivalent FeO6 octahedra, corners with three equivalent PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Fe–O bond distances ranging from 1.89–2.12 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 edges with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Fe–O bond distances ranging from 2.02–2.06 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 five FeO6 octahedra. The corner-sharing octahedra tilt angles range from 8–53°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra and an edgeedge with one FeO6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the second O site, O is bonded in a distorted T-shaped geometry to one Li, one Fe, and one P atom. In the third O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the fourth O site, O is bonded in a linear geometry to one Fe and one P atom. In the fifth O site, O is bonded in an L-shaped geometry to one Fe and one P atom. In the sixth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to two equivalent Fe and one P atom.