Materials Data on LiFePO4 by Materials Project

Abstract

LiFePO4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with six equivalent FeO6 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 75–77°. There are three shorter (2.05 Å) and one longer (2.19 Å) Li–O bond lengths. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent LiO4 tetrahedra, corners with six equivalent PO4 tetrahedra, and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.04–2.33 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with six equivalent FeO6 octahedra and corners with four equivalent LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–54°. There are a spread of P–O bond distances ranging from 1.55–1.58 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe2+, and one P5+ atom. In the second O2- site, O2- is bonded to one Li1+, two equivalent Fe2+, and one P5+ atom to form distorted corner-sharing OLiFe2P tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent Fe2+, and one P5+ atom.