ZnCo2O4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(4), two equivalent O(2), and three equivalent O(3) atoms to form CoO6 octahedra that share corners with four equivalent Co(2)O6 octahedra, corners with four equivalent Zn(1)O7 pentagonal bipyramids, edges with four equivalent Co(1)O6 octahedra, and edges with three equivalent Zn(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 52-63°. In the second Co site, Co(2) is bonded to one O(2), two equivalent O(4), and three equivalent O(1) atoms to form CoO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, corners with six equivalent Zn(1)O7 pentagonal bipyramids, edges with four equivalent Co(2)O6 octahedra,  an edgeedge with one Zn(1)O7 pentagonal bipyramid, and  a faceface with one Zn(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 52-63°. Zn(1) is bonded to one O(2), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted ZnO7 pentagonal bipyramids that share corners with four equivalent Co(1)O6 octahedra, corners with six equivalent Co(2)O6 octahedra,  an edgeedge with one Co(2)O6 octahedra, edges with three equivalent Co(1)O6 octahedra,  a faceface with one Co(2)O6 octahedra, and faces with two equivalent Zn(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 28-70°. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Co(2) and two equivalent Zn(1) atoms to form distorted OZn2Co3 trigonal bipyramids that share corners with two equivalent O(3)Zn2Co3 trigonal bipyramids, corners with six equivalent O(4)Zn2Co3 trigonal bipyramids,  a cornercorner with one O(2)ZnCo3 trigonal pyramid,  an edgeedge with one O(3)Zn2Co3 trigonal bipyramid, edges with two equivalent O(4)Zn2Co3 trigonal bipyramids, edges with four equivalent O(1)Zn2Co3 trigonal bipyramids, and edges with two equivalent O(2)ZnCo3 trigonal pyramids. In the second O site, O(2) is bonded to one Co(2), two equivalent Co(1), and one Zn(1) atom to form distorted OZnCo3 trigonal pyramids that share  a cornercorner with one O(1)Zn2Co3 trigonal bipyramid, corners with two equivalent O(4)Zn2Co3 trigonal bipyramids, corners with six equivalent O(3)Zn2Co3 trigonal bipyramids, corners with two equivalent O(2)ZnCo3 trigonal pyramids,  an edgeedge with one O(3)Zn2Co3 trigonal bipyramid, edges with two equivalent O(1)Zn2Co3 trigonal bipyramids, and edges with two equivalent O(4)Zn2Co3 trigonal bipyramids. In the third O site, O(3) is bonded to three equivalent Co(1) and two equivalent Zn(1) atoms to form distorted OZn2Co3 trigonal bipyramids that share corners with two equivalent O(1)Zn2Co3 trigonal bipyramids, corners with five equivalent O(4)Zn2Co3 trigonal bipyramids, corners with six equivalent O(2)ZnCo3 trigonal pyramids,  an edgeedge with one O(1)Zn2Co3 trigonal bipyramid,  an edgeedge with one O(4)Zn2Co3 trigonal bipyramid, edges with four equivalent O(3)Zn2Co3 trigonal bipyramids, and  an edgeedge with one O(2)ZnCo3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Co(1), two equivalent Co(2), and two equivalent Zn(1) atoms to form distorted OZn2Co3 trigonal bipyramids that share corners with five equivalent O(3)Zn2Co3 trigonal bipyramids, corners with six equivalent O(1)Zn2Co3 trigonal bipyramids, corners with two equivalent O(2)ZnCo3 trigonal pyramids,  an edgeedge with one O(3)Zn2Co3 trigonal bipyramid, edges with two equivalent O(1)Zn2Co3 trigonal bipyramids, edges with two equivalent O(4)Zn2Co3 trigonal bipyramids, and edges with two equivalent O(2)ZnCo3 trigonal pyramids.
ZnCo2O4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(4), two equivalent O(2), and three equivalent O(3) atoms to form CoO6 octahedra that share corners with four equivalent Co(2)O6 octahedra, corners with four equivalent Zn(1)O7 pentagonal bipyramids, edges with four equivalent Co(1)O6 octahedra, and edges with three equivalent Zn(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 52-63°. The Co(1)-O(4) bond length is 2.09 Å. Both Co(1)-O(2) bond lengths are 1.95 Å. There is one shorter (2.01 Å) and two longer (2.12 Å) Co(1)-O(3) bond lengths. In the second Co site, Co(2) is bonded to one O(2), two equivalent O(4), and three equivalent O(1) atoms to form CoO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, corners with six equivalent Zn(1)O7 pentagonal bipyramids, edges with four equivalent Co(2)O6 octahedra,  an edgeedge with one Zn(1)O7 pentagonal bipyramid, and  a faceface with one Zn(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 52-63°. The Co(2)-O(2) bond length is 1.98 Å. Both Co(2)-O(4) bond lengths are 2.04 Å. There is one shorter (1.88 Å) and two longer (2.13 Å) Co(2)-O(1) bond lengths. Zn(1) is bonded to one O(2), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted ZnO7 pentagonal bipyramids that share corners with four equivalent Co(1)O6 octahedra, corners with six equivalent Co(2)O6 octahedra,  an edgeedge with one Co(2)O6 octahedra, edges with three equivalent Co(1)O6 octahedra,  a faceface with one Co(2)O6 octahedra, and faces with two equivalent Zn(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 28-70°. The Zn(1)-O(2) bond length is 2.19 Å. Both Zn(1)-O(1) bond lengths are 2.28 Å. Both Zn(1)-O(3) bond lengths are 2.23 Å. Both Zn(1)-O(4) bond lengths are 2.31 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Co(2) and two equivalent Zn(1) atoms to form distorted OZn2Co3 trigonal bipyramids that share corners with two equivalent O(3)Zn2Co3 trigonal bipyramids, corners with six equivalent O(4)Zn2Co3 trigonal bipyramids,  a cornercorner with one O(2)ZnCo3 trigonal pyramid,  an edgeedge with one O(3)Zn2Co3 trigonal bipyramid, edges with two equivalent O(4)Zn2Co3 trigonal bipyramids, edges with four equivalent O(1)Zn2Co3 trigonal bipyramids, and edges with two equivalent O(2)ZnCo3 trigonal pyramids. In the second O site, O(2) is bonded to one Co(2), two equivalent Co(1), and one Zn(1) atom to form distorted OZnCo3 trigonal pyramids that share  a cornercorner with one O(1)Zn2Co3 trigonal bipyramid, corners with two equivalent O(4)Zn2Co3 trigonal bipyramids, corners with six equivalent O(3)Zn2Co3 trigonal bipyramids, corners with two equivalent O(2)ZnCo3 trigonal pyramids,  an edgeedge with one O(3)Zn2Co3 trigonal bipyramid, edges with two equivalent O(1)Zn2Co3 trigonal bipyramids, and edges with two equivalent O(4)Zn2Co3 trigonal bipyramids. In the third O site, O(3) is bonded to three equivalent Co(1) and two equivalent Zn(1) atoms to form distorted OZn2Co3 trigonal bipyramids that share corners with two equivalent O(1)Zn2Co3 trigonal bipyramids, corners with five equivalent O(4)Zn2Co3 trigonal bipyramids, corners with six equivalent O(2)ZnCo3 trigonal pyramids,  an edgeedge with one O(1)Zn2Co3 trigonal bipyramid,  an edgeedge with one O(4)Zn2Co3 trigonal bipyramid, edges with four equivalent O(3)Zn2Co3 trigonal bipyramids, and  an edgeedge with one O(2)ZnCo3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Co(1), two equivalent Co(2), and two equivalent Zn(1) atoms to form distorted OZn2Co3 trigonal bipyramids that share corners with five equivalent O(3)Zn2Co3 trigonal bipyramids, corners with six equivalent O(1)Zn2Co3 trigonal bipyramids, corners with two equivalent O(2)ZnCo3 trigonal pyramids,  an edgeedge with one O(3)Zn2Co3 trigonal bipyramid, edges with two equivalent O(1)Zn2Co3 trigonal bipyramids, edges with two equivalent O(4)Zn2Co3 trigonal bipyramids, and edges with two equivalent O(2)ZnCo3 trigonal pyramids.