Materials Data on CaAlBO4 by Materials Project
CaAlBO4 crystallizes in the orthorhombic Ccc2 space group. The structure is three-dimensional. Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.69 Å. Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.80 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.37 Å) and two longer (1.39 Å) B–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one B3+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to one Ca2+ and two equivalent Al3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Al3+, and one B3+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent Ca2+ and one B3+ atom.