CuMn2O4 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(4) and three equivalent O(3) atoms to form MnO4 tetrahedra that share corners with three equivalent Cu(2)O6 octahedra and corners with nine equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-62°. In the second Mn site, Mn(2) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with three equivalent Mn(1)O4 tetrahedra, corners with three equivalent Cu(1)O4 tetrahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1) and three equivalent O(2) atoms to form CuO4 tetrahedra that share corners with three equivalent Cu(2)O6 octahedra and corners with nine equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-61°. In the second Cu site, Cu(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form CuO6 octahedra that share corners with three equivalent Mn(1)O4 tetrahedra, corners with three equivalent Cu(1)O4 tetrahedra, and edges with six equivalent Mn(2)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to three equivalent Mn(2) and one Cu(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mn(2), one Cu(1), and one Cu(2) atom. In the third O site, O(3) is bonded to one Mn(1), two equivalent Mn(2), and one Cu(2) atom to form distorted OMn3Cu trigonal pyramids that share  a cornercorner with one O(4)Mn4 trigonal pyramid, corners with two equivalent O(3)Mn3Cu trigonal pyramids,  an edgeedge with one O(4)Mn4 trigonal pyramid, and edges with two equivalent O(3)Mn3Cu trigonal pyramids. In the fourth O site, O(4) is bonded to one Mn(1) and three equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing OMn4 trigonal pyramids.
CuMn2O4 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(4) and three equivalent O(3) atoms to form MnO4 tetrahedra that share corners with three equivalent Cu(2)O6 octahedra and corners with nine equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-62°. The Mn(1)-O(4) bond length is 2.00 Å. All Mn(1)-O(3) bond lengths are 2.05 Å. In the second Mn site, Mn(2) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with three equivalent Mn(1)O4 tetrahedra, corners with three equivalent Cu(1)O4 tetrahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The Mn(2)-O(1) bond length is 2.08 Å. The Mn(2)-O(4) bond length is 2.07 Å. Both Mn(2)-O(2) bond lengths are 1.99 Å. Both Mn(2)-O(3) bond lengths are 2.00 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1) and three equivalent O(2) atoms to form CuO4 tetrahedra that share corners with three equivalent Cu(2)O6 octahedra and corners with nine equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-61°. The Cu(1)-O(1) bond length is 1.95 Å. All Cu(1)-O(2) bond lengths are 2.03 Å. In the second Cu site, Cu(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form CuO6 octahedra that share corners with three equivalent Mn(1)O4 tetrahedra, corners with three equivalent Cu(1)O4 tetrahedra, and edges with six equivalent Mn(2)O6 octahedra. All Cu(2)-O(2) bond lengths are 2.09 Å. All Cu(2)-O(3) bond lengths are 2.09 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to three equivalent Mn(2) and one Cu(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mn(2), one Cu(1), and one Cu(2) atom. In the third O site, O(3) is bonded to one Mn(1), two equivalent Mn(2), and one Cu(2) atom to form distorted OMn3Cu trigonal pyramids that share  a cornercorner with one O(4)Mn4 trigonal pyramid, corners with two equivalent O(3)Mn3Cu trigonal pyramids,  an edgeedge with one O(4)Mn4 trigonal pyramid, and edges with two equivalent O(3)Mn3Cu trigonal pyramids. In the fourth O site, O(4) is bonded to one Mn(1) and three equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing OMn4 trigonal pyramids.