Cr8MnCu3S16 is Spinel-derived structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(2), two equivalent S(1), and three equivalent S(3) atoms to form CrS6 octahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with two equivalent Mn(1)S4 tetrahedra, corners with three equivalent Cu(2)S4 tetrahedra, edges with two equivalent Cr(2)S6 octahedra, and edges with four equivalent Cr(1)S6 octahedra. In the second Cr site, Cr(2) is bonded to one S(1), two equivalent S(2), and three equivalent S(4) atoms to form CrS6 octahedra that share  a cornercorner with one Mn(1)S4 tetrahedra, corners with two equivalent Cu(1)S4 tetrahedra, corners with three equivalent Cu(2)S4 tetrahedra, edges with two equivalent Cr(1)S6 octahedra, and edges with four equivalent Cr(2)S6 octahedra. Mn(1) is bonded to four equivalent S(1) atoms to form MnS4 tetrahedra that share corners with four equivalent Cr(2)S6 octahedra and corners with eight equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Cr(1)S6 octahedra and corners with eight equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second Cu site, Cu(2) is bonded to two equivalent S(3) and two equivalent S(4) atoms to form CuS4 tetrahedra that share corners with six equivalent Cr(1)S6 octahedra and corners with six equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 56-57°. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Cr(2), two equivalent Cr(1), and one Mn(1) atom to form distorted SMnCr3 trigonal pyramids that share corners with three equivalent S(1)MnCr3 trigonal pyramids,  an edgeedge with one S(1)MnCr3 trigonal pyramid, and edges with two equivalent S(2)Cr3Cu trigonal pyramids. In the second S site, S(2) is bonded to one Cr(1), two equivalent Cr(2), and one Cu(1) atom to form distorted SCr3Cu trigonal pyramids that share corners with three equivalent S(2)Cr3Cu trigonal pyramids,  an edgeedge with one S(2)Cr3Cu trigonal pyramid, and edges with two equivalent S(1)MnCr3 trigonal pyramids. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to three equivalent Cr(1) and one Cu(2) atom. In the fourth S site, S(4) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr(2) and one Cu(2) atom.
Cr8MnCu3S16 is Spinel-derived structured and crystallizes in the tetragonal P-4m2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(2), two equivalent S(1), and three equivalent S(3) atoms to form CrS6 octahedra that share  a cornercorner with one Cu(1)S4 tetrahedra, corners with two equivalent Mn(1)S4 tetrahedra, corners with three equivalent Cu(2)S4 tetrahedra, edges with two equivalent Cr(2)S6 octahedra, and edges with four equivalent Cr(1)S6 octahedra. The Cr(1)-S(2) bond length is 2.40 Å. Both Cr(1)-S(1) bond lengths are 2.42 Å. There are two shorter (2.37 Å) and one longer (2.40 Å) Cr(1)-S(3) bond length. In the second Cr site, Cr(2) is bonded to one S(1), two equivalent S(2), and three equivalent S(4) atoms to form CrS6 octahedra that share  a cornercorner with one Mn(1)S4 tetrahedra, corners with two equivalent Cu(1)S4 tetrahedra, corners with three equivalent Cu(2)S4 tetrahedra, edges with two equivalent Cr(1)S6 octahedra, and edges with four equivalent Cr(2)S6 octahedra. The Cr(2)-S(1) bond length is 2.42 Å. Both Cr(2)-S(2) bond lengths are 2.40 Å. There is one shorter (2.36 Å) and two longer (2.40 Å) Cr(2)-S(4) bond lengths. Mn(1) is bonded to four equivalent S(1) atoms to form MnS4 tetrahedra that share corners with four equivalent Cr(2)S6 octahedra and corners with eight equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Mn(1)-S(1) bond lengths are 2.31 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Cr(1)S6 octahedra and corners with eight equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Cu(1)-S(2) bond lengths are 2.29 Å. In the second Cu site, Cu(2) is bonded to two equivalent S(3) and two equivalent S(4) atoms to form CuS4 tetrahedra that share corners with six equivalent Cr(1)S6 octahedra and corners with six equivalent Cr(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 56-57°. Both Cu(2)-S(3) bond lengths are 2.28 Å. Both Cu(2)-S(4) bond lengths are 2.28 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Cr(2), two equivalent Cr(1), and one Mn(1) atom to form distorted SMnCr3 trigonal pyramids that share corners with three equivalent S(1)MnCr3 trigonal pyramids,  an edgeedge with one S(1)MnCr3 trigonal pyramid, and edges with two equivalent S(2)Cr3Cu trigonal pyramids. In the second S site, S(2) is bonded to one Cr(1), two equivalent Cr(2), and one Cu(1) atom to form distorted SCr3Cu trigonal pyramids that share corners with three equivalent S(2)Cr3Cu trigonal pyramids,  an edgeedge with one S(2)Cr3Cu trigonal pyramid, and edges with two equivalent S(1)MnCr3 trigonal pyramids. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to three equivalent Cr(1) and one Cu(2) atom. In the fourth S site, S(4) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr(2) and one Cu(2) atom.