Ca2Al3O8 crystallizes in the cubic I-43m space group. Ca(1) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. Al(1) is bonded to four equivalent O(1) atoms to form corner-sharing AlO4 tetrahedra. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to three equivalent Ca(1) atoms. In the second O site, O(1) is bonded in a trigonal planar geometry to one Ca(1) and two equivalent Al(1) atoms.
Ca2Al3O8 crystallizes in the cubic I-43m space group. Ca(1) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. All Ca(1)-O(1) bond lengths are 2.29 Å. All Ca(1)-O(2) bond lengths are 2.57 Å. Al(1) is bonded to four equivalent O(1) atoms to form corner-sharing AlO4 tetrahedra. All Al(1)-O(1) bond lengths are 1.77 Å. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to three equivalent Ca(1) atoms. In the second O site, O(1) is bonded in a trigonal planar geometry to one Ca(1) and two equivalent Al(1) atoms.