Co5SbO8 is Spinel-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with three equivalent Co(3)O6 octahedra, corners with three equivalent Sb(1)O6 octahedra, and corners with six equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-63°. In the second Co site, Co(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Sb(1)O6 octahedra. In the third Co site, Co(3) 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 Sb(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. Sb(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form SbO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Co(1), one Co(3), and two equivalent Co(2) atoms to form OCo4 tetrahedra that share corners with three equivalent O(1)Co4 tetrahedra, corners with three equivalent O(3)Co3Sb trigonal pyramids, and  an edgeedge with one O(3)Co3Sb trigonal pyramid. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one Sb(1) atom. In the third O site, O(3) is bonded to one Co(1), two equivalent Co(2), and one Sb(1) atom to form distorted OCo3Sb trigonal pyramids that share corners with three equivalent O(1)Co4 tetrahedra, corners with three equivalent O(3)Co3Sb trigonal pyramids, and  an edgeedge with one O(1)Co4 tetrahedra.
Co5SbO8 is Spinel-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with three equivalent Co(3)O6 octahedra, corners with three equivalent Sb(1)O6 octahedra, and corners with six equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-63°. The Co(1)-O(1) bond length is 1.95 Å. The Co(1)-O(3) bond length is 1.98 Å. Both Co(1)-O(2) bond lengths are 1.98 Å. In the second Co site, Co(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Sb(1)O6 octahedra. Both Co(2)-O(1) bond lengths are 1.95 Å. Both Co(2)-O(2) bond lengths are 2.23 Å. Both Co(2)-O(3) bond lengths are 1.97 Å. In the third Co site, Co(3) 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 Sb(1)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. Both Co(3)-O(1) bond lengths are 1.94 Å. All Co(3)-O(2) bond lengths are 1.95 Å. Sb(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form SbO6 octahedra that share corners with six equivalent Co(1)O4 tetrahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Co(2)O6 octahedra. Both Sb(1)-O(3) bond lengths are 2.00 Å. All Sb(1)-O(2) bond lengths are 1.99 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Co(1), one Co(3), and two equivalent Co(2) atoms to form OCo4 tetrahedra that share corners with three equivalent O(1)Co4 tetrahedra, corners with three equivalent O(3)Co3Sb trigonal pyramids, and  an edgeedge with one O(3)Co3Sb trigonal pyramid. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one Sb(1) atom. In the third O site, O(3) is bonded to one Co(1), two equivalent Co(2), and one Sb(1) atom to form distorted OCo3Sb trigonal pyramids that share corners with three equivalent O(1)Co4 tetrahedra, corners with three equivalent O(3)Co3Sb trigonal pyramids, and  an edgeedge with one O(1)Co4 tetrahedra.