MgZn(CoO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(8) atoms to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Co(1)O6 octahedra,  a cornercorner with one Co(3)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 13-14°. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form distorted CoO6 octahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with two equivalent Mg(1)O5 trigonal bipyramids, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, edges with two equivalent Zn(1)O5 square pyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. In the second Co site, Co(2) is bonded to one O(4), one O(8), and two equivalent O(3) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra,  a cornercorner with one Zn(1)O5 square pyramid, corners with two equivalent Co(2)O4 tetrahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 52-60°. In the third Co site, Co(3) is bonded to one O(1), one O(6), and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with two equivalent Zn(1)O5 square pyramids, corners with two equivalent Co(3)O4 tetrahedra, and  a cornercorner with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 52-61°. In the fourth Co site, Co(4) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form distorted CoO6 octahedra that share corners with two equivalent Zn(1)O5 square pyramids, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra,  an edgeedge with one Zn(1)O5 square pyramid, and edges with two equivalent Mg(1)O5 trigonal bipyramids. Zn(1) is bonded to one O(4), two equivalent O(6), and two equivalent O(7) atoms to form distorted ZnO5 square pyramids that share corners with two equivalent Co(4)O6 octahedra,  a cornercorner with one Co(2)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra,  an edgeedge with one Co(4)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Zn(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 14°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(3), and two equivalent Co(4) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Co(1) and two equivalent Co(3) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Co(4) and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Co(2), two equivalent Co(1), and one Zn(1) atom. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one Co(4), and two equivalent Co(1) atoms to form distorted OMg2Co3 square pyramids that share edges with two equivalent O(5)Mg2Co3 square pyramids and edges with two equivalent O(7)Zn2Co3 square pyramids. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Co(3) and two equivalent Zn(1) atoms. In the seventh O site, O(7) is bonded to one Co(1), two equivalent Co(4), and two equivalent Zn(1) atoms to form OZn2Co3 square pyramids that share edges with two equivalent O(5)Mg2Co3 square pyramids and edges with two equivalent O(7)Zn2Co3 square pyramids. In the eighth O site, O(8) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one Co(2) atom.
MgZn(CoO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(8) atoms to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Co(1)O6 octahedra,  a cornercorner with one Co(3)O4 tetrahedra, corners with two equivalent Co(2)O4 tetrahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 13-14°. The Mg(1)-O(1) bond length is 2.07 Å. There is one shorter (2.15 Å) and one longer (2.18 Å) Mg(1)-O(5) bond length. Both Mg(1)-O(8) bond lengths are 1.99 Å. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form distorted CoO6 octahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, corners with two equivalent Mg(1)O5 trigonal bipyramids, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, edges with two equivalent Zn(1)O5 square pyramids, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The Co(1)-O(2) bond length is 1.86 Å. The Co(1)-O(7) bond length is 1.90 Å. There is one shorter (1.92 Å) and one longer (2.19 Å) Co(1)-O(4) bond length. There is one shorter (1.95 Å) and one longer (2.36 Å) Co(1)-O(5) bond length. In the second Co site, Co(2) is bonded to one O(4), one O(8), and two equivalent O(3) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra,  a cornercorner with one Zn(1)O5 square pyramid, corners with two equivalent Co(2)O4 tetrahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 52-60°. The Co(2)-O(4) bond length is 1.88 Å. The Co(2)-O(8) bond length is 1.77 Å. There is one shorter (1.90 Å) and one longer (1.92 Å) Co(2)-O(3) bond length. In the third Co site, Co(3) is bonded to one O(1), one O(6), and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with two equivalent Zn(1)O5 square pyramids, corners with two equivalent Co(3)O4 tetrahedra, and  a cornercorner with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 52-61°. The Co(3)-O(1) bond length is 1.86 Å. The Co(3)-O(6) bond length is 1.80 Å. Both Co(3)-O(2) bond lengths are 1.90 Å. In the fourth Co site, Co(4) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form distorted CoO6 octahedra that share corners with two equivalent Zn(1)O5 square pyramids, corners with two equivalent Co(2)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra,  an edgeedge with one Zn(1)O5 square pyramid, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The Co(4)-O(3) bond length is 1.85 Å. The Co(4)-O(5) bond length is 1.92 Å. There is one shorter (1.93 Å) and one longer (2.20 Å) Co(4)-O(1) bond length. There is one shorter (1.96 Å) and one longer (2.32 Å) Co(4)-O(7) bond length. Zn(1) is bonded to one O(4), two equivalent O(6), and two equivalent O(7) atoms to form distorted ZnO5 square pyramids that share corners with two equivalent Co(4)O6 octahedra,  a cornercorner with one Co(2)O4 tetrahedra, corners with two equivalent Co(3)O4 tetrahedra,  an edgeedge with one Co(4)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Zn(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 14°. The Zn(1)-O(4) bond length is 2.09 Å. There is one shorter (1.96 Å) and one longer (1.97 Å) Zn(1)-O(6) bond length. There is one shorter (2.18 Å) and one longer (2.25 Å) Zn(1)-O(7) bond length. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(3), and two equivalent Co(4) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Co(1) and two equivalent Co(3) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Co(4) and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Co(2), two equivalent Co(1), and one Zn(1) atom. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one Co(4), and two equivalent Co(1) atoms to form distorted OMg2Co3 square pyramids that share edges with two equivalent O(5)Mg2Co3 square pyramids and edges with two equivalent O(7)Zn2Co3 square pyramids. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Co(3) and two equivalent Zn(1) atoms. In the seventh O site, O(7) is bonded to one Co(1), two equivalent Co(4), and two equivalent Zn(1) atoms to form OZn2Co3 square pyramids that share edges with two equivalent O(5)Mg2Co3 square pyramids and edges with two equivalent O(7)Zn2Co3 square pyramids. In the eighth O site, O(8) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one Co(2) atom.