Materials Data on Li2Fe3(P2O7)2 by Materials Project

Abstract

Li2Fe3(P2O7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.98–2.09 Å. There are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to five O2- atoms to form FeO5 square pyramids that share a cornercorner with one FeO6 octahedra, corners with five PO4 tetrahedra, and an edgeedge with one FeO5 square pyramid. The corner-sharing octahedral tilt angles are 73°. There are a spread of Fe–O bond distances ranging from 2.09–2.20 Å. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO5 square pyramids and corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.19–2.23 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 a cornercorner with one FeO6 octahedra, corners with three equivalent FeO5 square pyramids, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent FeO5 square pyramids, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–57°. There are a spread of P–O bond distances ranging from 1.52–1.61 Å. There are seven 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 in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms.