Materials Data on LiAlPO4F by Materials Project
LiAlPO4F crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li1+ is bonded in a 6-coordinate geometry to five O2- and one F1- atom. There are a spread of Li–O bond distances ranging from 2.05–2.46 Å. The Li–F bond length is 1.95 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- and two equivalent F1- atoms to form AlO4F2 octahedra that share corners with two equivalent AlO4F2 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 40°. All Al–O bond lengths are 1.89 Å. Both Al–F bond lengths are 1.86 Å. In the second Al3+ site, Al3+ is bonded to four O2- and two equivalent F1- atoms to form AlO4F2 octahedra that share corners with two equivalent AlO4F2 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 40°. There is two shorter (1.86 Å) and two longer (1.90 Å) Al–O bond length. Both Al–F bond lengths are 1.86 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four AlO4F2 octahedra. The corner-sharing octahedra tilt angles range from 27–50°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Li1+, one Al3+, and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Al3+, and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Al3+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Al3+, and one P5+ atom. F1- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and two Al3+ atoms.