ZnCrO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Cr site, Cr(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted CrO5 trigonal bipyramids that share corners with four equivalent Zn(2)O4 tetrahedra, corners with two equivalent Zn(1)O5 trigonal bipyramids,  an edgeedge with one Zn(2)O4 tetrahedra, edges with two equivalent Cr(2)O5 trigonal bipyramids, and  a faceface with one Zn(1)O5 trigonal bipyramid. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted ZnO5 trigonal bipyramids that share corners with four equivalent Zn(2)O4 tetrahedra, corners with two equivalent Cr(2)O5 trigonal bipyramids, edges with two equivalent Zn(1)O5 trigonal bipyramids, and  a faceface with one Cr(2)O5 trigonal bipyramid. In the second Zn site, Zn(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form ZnO4 tetrahedra that share corners with two equivalent Zn(2)O4 tetrahedra, corners with four equivalent Cr(2)O5 trigonal bipyramids, corners with four equivalent Zn(1)O5 trigonal bipyramids, and  an edgeedge with one Cr(2)O5 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Cr(2), two equivalent Cr(1), and one Zn(1) atom to form distorted OZnCr3 tetrahedra that share corners with two equivalent O(1)ZnCr3 tetrahedra, corners with four equivalent O(3)Zn3Cr2 trigonal bipyramids,  an edgeedge with one O(3)Zn3Cr2 trigonal bipyramid, and edges with two equivalent O(4)Zn3Cr2 trigonal bipyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to two equivalent Cr(2) and two equivalent Zn(2) atoms. In the third O site, O(3) is bonded to two equivalent Cr(1), one Zn(2), and two equivalent Zn(1) atoms to form distorted OZn3Cr2 trigonal bipyramids that share corners with four equivalent O(1)ZnCr3 tetrahedra, corners with three equivalent O(4)Zn3Cr2 trigonal bipyramids,  an edgeedge with one O(1)ZnCr3 tetrahedra,  an edgeedge with one O(4)Zn3Cr2 trigonal bipyramid, and edges with two equivalent O(3)Zn3Cr2 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Cr(2), one Zn(2), and two equivalent Zn(1) atoms to form distorted OZn3Cr2 trigonal bipyramids that share corners with three equivalent O(3)Zn3Cr2 trigonal bipyramids, edges with two equivalent O(1)ZnCr3 tetrahedra,  an edgeedge with one O(3)Zn3Cr2 trigonal bipyramid, and edges with two equivalent O(4)Zn3Cr2 trigonal bipyramids.
ZnCrO2 crystallizes in the triclinic P-1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. Both Cr(1)-O(1) bond lengths are 1.98 Å. Both Cr(1)-O(3) bond lengths are 2.17 Å. In the second Cr site, Cr(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted CrO5 trigonal bipyramids that share corners with four equivalent Zn(2)O4 tetrahedra, corners with two equivalent Zn(1)O5 trigonal bipyramids,  an edgeedge with one Zn(2)O4 tetrahedra, edges with two equivalent Cr(2)O5 trigonal bipyramids, and  a faceface with one Zn(1)O5 trigonal bipyramid. The Cr(2)-O(1) bond length is 2.26 Å. Both Cr(2)-O(2) bond lengths are 2.07 Å. There is one shorter (2.17 Å) and one longer (2.18 Å) Cr(2)-O(4) bond length. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted ZnO5 trigonal bipyramids that share corners with four equivalent Zn(2)O4 tetrahedra, corners with two equivalent Cr(2)O5 trigonal bipyramids, edges with two equivalent Zn(1)O5 trigonal bipyramids, and  a faceface with one Cr(2)O5 trigonal bipyramid. The Zn(1)-O(1) bond length is 2.01 Å. Both Zn(1)-O(3) bond lengths are 2.15 Å. There is one shorter (2.16 Å) and one longer (2.17 Å) Zn(1)-O(4) bond length. In the second Zn site, Zn(2) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form ZnO4 tetrahedra that share corners with two equivalent Zn(2)O4 tetrahedra, corners with four equivalent Cr(2)O5 trigonal bipyramids, corners with four equivalent Zn(1)O5 trigonal bipyramids, and  an edgeedge with one Cr(2)O5 trigonal bipyramid. The Zn(2)-O(3) bond length is 1.99 Å. The Zn(2)-O(4) bond length is 1.97 Å. Both Zn(2)-O(2) bond lengths are 2.03 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Cr(2), two equivalent Cr(1), and one Zn(1) atom to form distorted OZnCr3 tetrahedra that share corners with two equivalent O(1)ZnCr3 tetrahedra, corners with four equivalent O(3)Zn3Cr2 trigonal bipyramids,  an edgeedge with one O(3)Zn3Cr2 trigonal bipyramid, and edges with two equivalent O(4)Zn3Cr2 trigonal bipyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to two equivalent Cr(2) and two equivalent Zn(2) atoms. In the third O site, O(3) is bonded to two equivalent Cr(1), one Zn(2), and two equivalent Zn(1) atoms to form distorted OZn3Cr2 trigonal bipyramids that share corners with four equivalent O(1)ZnCr3 tetrahedra, corners with three equivalent O(4)Zn3Cr2 trigonal bipyramids,  an edgeedge with one O(1)ZnCr3 tetrahedra,  an edgeedge with one O(4)Zn3Cr2 trigonal bipyramid, and edges with two equivalent O(3)Zn3Cr2 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Cr(2), one Zn(2), and two equivalent Zn(1) atoms to form distorted OZn3Cr2 trigonal bipyramids that share corners with three equivalent O(3)Zn3Cr2 trigonal bipyramids, edges with two equivalent O(1)ZnCr3 tetrahedra,  an edgeedge with one O(3)Zn3Cr2 trigonal bipyramid, and edges with two equivalent O(4)Zn3Cr2 trigonal bipyramids.