Materials Data on LiCo2P2O9 by Materials Project
LiCo2P2O9 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.32 Å. There are two inequivalent Co+3.50+ sites. In the first Co+3.50+ site, Co+3.50+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with three equivalent PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Co–O bond distances ranging from 1.86–1.93 Å. In the second Co+3.50+ site, Co+3.50+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with four PO4 tetrahedra, and edges with two equivalent CoO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There is four shorter (1.92 Å) and two longer (1.95 Å) Co–O bond length. 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 five CoO6 octahedra. The corner-sharing octahedra tilt angles range from 17–55°. There are a spread of P–O bond distances ranging from 1.50–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent CoO6 octahedra and an edgeedge with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three Co+3.50+ atoms. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Co+3.50+, and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co+3.50+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Co+3.50+ and one P5+ atom. In the fifth O2- site, O2- is bonded in an L-shaped geometry to one Co+3.50+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Co+3.50+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Co+3.50+ and one P5+ atom.