Materials Data on LiTiPO4F by Materials Project
LiTiPO4F crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li1+ is bonded to four O2- and one F1- atom to form distorted LiO4F square pyramids that share corners with two equivalent TiO4F2 octahedra, corners with two equivalent PO4 tetrahedra, edges with two equivalent TiO4F2 octahedra, an edgeedge with one LiO4F square pyramid, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–60°. There are a spread of Li–O bond distances ranging from 2.11–2.21 Å. The Li–F bond length is 1.94 Å. There are two inequivalent Ti3+ sites. In the first Ti3+ site, Ti3+ is bonded to four O2- and two equivalent F1- atoms to form TiO4F2 octahedra that share corners with two equivalent TiO4F2 octahedra, corners with four equivalent PO4 tetrahedra, and edges with four equivalent LiO4F square pyramids. The corner-sharing octahedral tilt angles are 49°. There are two shorter (1.96 Å) and two longer (2.11 Å) Ti–O bond lengths. Both Ti–F bond lengths are 2.04 Å. In the second Ti3+ site, Ti3+ is bonded to four O2- and two equivalent F1- atoms to form TiO4F2 octahedra that share corners with two equivalent TiO4F2 octahedra, corners with four equivalent LiO4F square pyramids, and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There are two shorter (2.02 Å) and two longer (2.05 Å) Ti–O bond lengths. Both Ti–F bond lengths are 2.04 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four TiO4F2 octahedra, corners with two equivalent LiO4F square pyramids, and an edgeedge with one LiO4F square pyramid. The corner-sharing octahedra tilt angles range from 30–54°. There is one shorter (1.52 Å) and three longer (1.56 Å) P–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Ti3+, and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ti3+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Ti3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two equivalent Li1+, one Ti3+, and one P5+ atom. F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Ti3+ atoms.