CaCo4O9 crystallizes in the tetragonal P4/n space group. Ca(1) is bonded in a 8-coordinate geometry to four equivalent O(2) and four equivalent O(3) atoms. Co(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), and three equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted square co-planar geometry to four equivalent Co(1) atoms. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ca(1) and one Co(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1) and three equivalent Co(1) atoms.
CaCo4O9 crystallizes in the tetragonal P4/n space group. Ca(1) is bonded in a 8-coordinate geometry to four equivalent O(2) and four equivalent O(3) atoms. All Ca(1)-O(2) bond lengths are 2.39 Å. All Ca(1)-O(3) bond lengths are 2.53 Å. Co(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), and three equivalent O(3) atoms. The Co(1)-O(1) bond length is 2.00 Å. The Co(1)-O(2) bond length is 1.65 Å. There are a spread of Co(1)-O(3) bond distances ranging from 1.91-1.98 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted square co-planar geometry to four equivalent Co(1) atoms. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ca(1) and one Co(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1) and three equivalent Co(1) atoms.