Materials Data on LiTi2P2O9 by Materials Project
LiTi2P2O9 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li1+ is bonded in a 1-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.97–2.74 Å. There are two inequivalent Ti+3.50+ sites. In the first Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with three equivalent PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ti–O bond distances ranging from 1.89–2.13 Å. In the second Ti+3.50+ site, Ti+3.50+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra, corners with four PO4 tetrahedra, and edges with two equivalent TiO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ti–O bond distances ranging from 2.00–2.09 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 five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 5–51°. There is three shorter (1.53 Å) and one longer (1.58 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent TiO6 octahedra and an edgeedge with one TiO6 octahedra. The corner-sharing octahedral tilt angles are 48°. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+ and three Ti+3.50+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ti+3.50+, and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ti+3.50+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a linear geometry to one Ti+3.50+ and one P5+ atom. In the fifth O2- site, O2- is bonded in an L-shaped geometry to one Ti+3.50+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+, one Ti+3.50+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ti+3.50+ and one P5+ atom.