Materials Data on Al6B5(O5F)3 by Materials Project
Al6B5(O5F)3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Al3+ is bonded to five O2- and one F1- atom to form a mixture of edge and corner-sharing AlO5F octahedra. The corner-sharing octahedral tilt angles are 65°. There are a spread of Al–O bond distances ranging from 1.88–1.96 Å. The Al–F bond length is 1.83 Å. There are two inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.37 Å. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.38 Å) and two longer (1.40 Å) B–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Al3+ and one B3+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Al3+ and one B3+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Al3+ and one B3+ atom. F1- is bonded in a water-like geometry to two equivalent Al3+ atoms.