CaCo2O4 is Spinel-like structured and crystallizes in the orthorhombic Imma space group. Ca(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CaO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with six equivalent Ca(1)O6 octahedra and corners with six equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-60°. In the second Co site, Co(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Co(1), and two equivalent Co(2) atoms.
CaCo2O4 is Spinel-like structured and crystallizes in the orthorhombic Imma space group. Ca(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CaO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. Both Ca(1)-O(2) bond lengths are 2.28 Å. All Ca(1)-O(1) bond lengths are 2.27 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with six equivalent Ca(1)O6 octahedra and corners with six equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-60°. Both Co(1)-O(1) bond lengths are 1.88 Å. Both Co(1)-O(2) bond lengths are 1.96 Å. In the second Co site, Co(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. Both Co(2)-O(1) bond lengths are 1.98 Å. All Co(2)-O(2) bond lengths are 2.14 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Co(1), and two equivalent Co(2) atoms.