Materials Data on Li2CrP2O7 by Materials Project
Li2CrP2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two equivalent CrO6 octahedra, corners with four PO4 tetrahedra, an edgeedge with one CrO6 octahedra, and an edgeedge with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 68–77°. There are a spread of Li–O bond distances ranging from 1.92–2.09 Å. In the second Li1+ site, Li1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.01–2.76 Å. Cr2+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent LiO4 tetrahedra, corners with six PO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Cr–O bond distances ranging from 2.04–2.44 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 corners with three equivalent CrO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–59°. There are a spread of P–O bond distances ranging from 1.52–1.64 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent CrO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with three equivalent LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–61°. There are a spread of P–O bond distances ranging from 1.53–1.62 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 Cr2+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Cr2+, and one P5+ atom. In the third O2- site, O2- is bonded to two equivalent Li1+, one Cr2+, and one P5+ atom to form distorted edge-sharing OLi2CrP tetrahedra. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Li1+, one Cr2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Cr2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Cr2+, and one P5+ atom.