MgMnCoS4 is Spinel-derived structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form MgS4 tetrahedra that share corners with three equivalent Mn(1)S6 octahedra, corners with three equivalent Mn(2)S6 octahedra, and corners with six equivalent Co(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form MnS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mn(2)S6 octahedra, and edges with four equivalent Co(1)S6 octahedra. In the second Mn site, Mn(2) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form MnS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mn(1)S6 octahedra, and edges with four equivalent Co(1)S6 octahedra. Co(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form CoS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mn(1)S6 octahedra, edges with two equivalent Mn(2)S6 octahedra, and edges with two equivalent Co(1)S6 octahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one Mn(1), one Mn(2), and one Co(1) atom to form distorted SMgMn2Co tetrahedra that share corners with three equivalent S(2)MgMnCo2 tetrahedra, corners with three equivalent S(3)MgMnCo2 tetrahedra, corners with six equivalent S(1)MgMn2Co tetrahedra,  an edgeedge with one S(1)MgMn2Co tetrahedra,  an edgeedge with one S(2)MgMnCo2 tetrahedra, and  an edgeedge with one S(3)MgMnCo2 tetrahedra. In the second S site, S(2) is bonded to one Mg(1), one Mn(2), and two equivalent Co(1) atoms to form distorted SMgMnCo2 tetrahedra that share corners with three equivalent S(2)MgMnCo2 tetrahedra, corners with three equivalent S(3)MgMnCo2 tetrahedra, corners with six equivalent S(1)MgMn2Co tetrahedra,  an edgeedge with one S(3)MgMnCo2 tetrahedra, and edges with two equivalent S(1)MgMn2Co tetrahedra. In the third S site, S(3) is bonded to one Mg(1), one Mn(1), and two equivalent Co(1) atoms to form distorted SMgMnCo2 tetrahedra that share corners with three equivalent S(2)MgMnCo2 tetrahedra, corners with three equivalent S(3)MgMnCo2 tetrahedra, corners with six equivalent S(1)MgMn2Co tetrahedra,  an edgeedge with one S(2)MgMnCo2 tetrahedra, and edges with two equivalent S(1)MgMn2Co tetrahedra.
MgMnCoS4 is Spinel-derived structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one S(2), one S(3), and two equivalent S(1) atoms to form MgS4 tetrahedra that share corners with three equivalent Mn(1)S6 octahedra, corners with three equivalent Mn(2)S6 octahedra, and corners with six equivalent Co(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. The Mg(1)-S(2) bond length is 2.43 Å. The Mg(1)-S(3) bond length is 2.43 Å. Both Mg(1)-S(1) bond lengths are 2.44 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form MnS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mn(2)S6 octahedra, and edges with four equivalent Co(1)S6 octahedra. Both Mn(1)-S(3) bond lengths are 2.34 Å. All Mn(1)-S(1) bond lengths are 2.35 Å. In the second Mn site, Mn(2) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form MnS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mn(1)S6 octahedra, and edges with four equivalent Co(1)S6 octahedra. Both Mn(2)-S(2) bond lengths are 2.34 Å. All Mn(2)-S(1) bond lengths are 2.35 Å. Co(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form CoS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mn(1)S6 octahedra, edges with two equivalent Mn(2)S6 octahedra, and edges with two equivalent Co(1)S6 octahedra. Both Co(1)-S(1) bond lengths are 2.29 Å. Both Co(1)-S(2) bond lengths are 2.31 Å. Both Co(1)-S(3) bond lengths are 2.31 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one Mn(1), one Mn(2), and one Co(1) atom to form distorted SMgMn2Co tetrahedra that share corners with three equivalent S(2)MgMnCo2 tetrahedra, corners with three equivalent S(3)MgMnCo2 tetrahedra, corners with six equivalent S(1)MgMn2Co tetrahedra,  an edgeedge with one S(1)MgMn2Co tetrahedra,  an edgeedge with one S(2)MgMnCo2 tetrahedra, and  an edgeedge with one S(3)MgMnCo2 tetrahedra. In the second S site, S(2) is bonded to one Mg(1), one Mn(2), and two equivalent Co(1) atoms to form distorted SMgMnCo2 tetrahedra that share corners with three equivalent S(2)MgMnCo2 tetrahedra, corners with three equivalent S(3)MgMnCo2 tetrahedra, corners with six equivalent S(1)MgMn2Co tetrahedra,  an edgeedge with one S(3)MgMnCo2 tetrahedra, and edges with two equivalent S(1)MgMn2Co tetrahedra. In the third S site, S(3) is bonded to one Mg(1), one Mn(1), and two equivalent Co(1) atoms to form distorted SMgMnCo2 tetrahedra that share corners with three equivalent S(2)MgMnCo2 tetrahedra, corners with three equivalent S(3)MgMnCo2 tetrahedra, corners with six equivalent S(1)MgMn2Co tetrahedra,  an edgeedge with one S(2)MgMnCo2 tetrahedra, and edges with two equivalent S(1)MgMn2Co tetrahedra.