Mg2V3CrS8 is Spinel-derived structured and crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one S(1), one S(2), one S(3), and one S(4) atom to form MgS4 tetrahedra that share corners with three equivalent V(1)S6 octahedra, corners with three equivalent V(2)S6 octahedra, corners with three equivalent V(3)S6 octahedra, and corners with three equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 58-60°. There are three inequivalent V sites. In the first V site, V(1) is bonded to two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form VS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, and edges with two equivalent Cr(1)S6 octahedra. In the second V site, V(2) is bonded to two equivalent S(1), two equivalent S(3), and two equivalent S(4) atoms to form VS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(3)S6 octahedra, and edges with two equivalent Cr(1)S6 octahedra. In the third V site, V(3) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form VS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and edges with two equivalent Cr(1)S6 octahedra. Cr(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(4) atoms to form CrS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and edges with two equivalent V(3)S6 octahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one V(2), one V(3), and one Cr(1) atom to form distorted SMgV2Cr trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(2)MgV2Cr trigonal pyramid,  an edgeedge with one S(4)MgV2Cr trigonal pyramid, and  an edgeedge with one S(3)MgV3 trigonal pyramid. In the second S site, S(2) is bonded to one Mg(1), one V(1), one V(3), and one Cr(1) atom to form distorted SMgV2Cr trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(1)MgV2Cr trigonal pyramid,  an edgeedge with one S(4)MgV2Cr trigonal pyramid, and  an edgeedge with one S(3)MgV3 trigonal pyramid. In the third S site, S(3) is bonded to one Mg(1), one V(1), one V(2), and one V(3) atom to form distorted SMgV3 trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(1)MgV2Cr trigonal pyramid,  an edgeedge with one S(2)MgV2Cr trigonal pyramid, and  an edgeedge with one S(4)MgV2Cr trigonal pyramid. In the fourth S site, S(4) is bonded to one Mg(1), one V(1), one V(2), and one Cr(1) atom to form distorted SMgV2Cr trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(1)MgV2Cr trigonal pyramid,  an edgeedge with one S(2)MgV2Cr trigonal pyramid, and  an edgeedge with one S(3)MgV3 trigonal pyramid.
Mg2V3CrS8 is Spinel-derived structured and crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one S(1), one S(2), one S(3), and one S(4) atom to form MgS4 tetrahedra that share corners with three equivalent V(1)S6 octahedra, corners with three equivalent V(2)S6 octahedra, corners with three equivalent V(3)S6 octahedra, and corners with three equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 58-60°. The Mg(1)-S(1) bond length is 2.42 Å. The Mg(1)-S(2) bond length is 2.43 Å. The Mg(1)-S(3) bond length is 2.45 Å. The Mg(1)-S(4) bond length is 2.42 Å. There are three inequivalent V sites. In the first V site, V(1) is bonded to two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form VS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, and edges with two equivalent Cr(1)S6 octahedra. Both V(1)-S(2) bond lengths are 2.45 Å. Both V(1)-S(3) bond lengths are 2.44 Å. Both V(1)-S(4) bond lengths are 2.45 Å. In the second V site, V(2) is bonded to two equivalent S(1), two equivalent S(3), and two equivalent S(4) atoms to form VS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(3)S6 octahedra, and edges with two equivalent Cr(1)S6 octahedra. Both V(2)-S(1) bond lengths are 2.46 Å. Both V(2)-S(3) bond lengths are 2.45 Å. Both V(2)-S(4) bond lengths are 2.45 Å. In the third V site, V(3) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form VS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and edges with two equivalent Cr(1)S6 octahedra. Both V(3)-S(1) bond lengths are 2.45 Å. Both V(3)-S(2) bond lengths are 2.45 Å. Both V(3)-S(3) bond lengths are 2.45 Å. Cr(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(4) atoms to form CrS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and edges with two equivalent V(3)S6 octahedra. Both Cr(1)-S(1) bond lengths are 2.43 Å. Both Cr(1)-S(2) bond lengths are 2.43 Å. Both Cr(1)-S(4) bond lengths are 2.43 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one V(2), one V(3), and one Cr(1) atom to form distorted SMgV2Cr trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(2)MgV2Cr trigonal pyramid,  an edgeedge with one S(4)MgV2Cr trigonal pyramid, and  an edgeedge with one S(3)MgV3 trigonal pyramid. In the second S site, S(2) is bonded to one Mg(1), one V(1), one V(3), and one Cr(1) atom to form distorted SMgV2Cr trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(1)MgV2Cr trigonal pyramid,  an edgeedge with one S(4)MgV2Cr trigonal pyramid, and  an edgeedge with one S(3)MgV3 trigonal pyramid. In the third S site, S(3) is bonded to one Mg(1), one V(1), one V(2), and one V(3) atom to form distorted SMgV3 trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(1)MgV2Cr trigonal pyramid,  an edgeedge with one S(2)MgV2Cr trigonal pyramid, and  an edgeedge with one S(4)MgV2Cr trigonal pyramid. In the fourth S site, S(4) is bonded to one Mg(1), one V(1), one V(2), and one Cr(1) atom to form distorted SMgV2Cr trigonal pyramids that share corners with three equivalent S(1)MgV2Cr trigonal pyramids, corners with three equivalent S(2)MgV2Cr trigonal pyramids, corners with three equivalent S(4)MgV2Cr trigonal pyramids, corners with three equivalent S(3)MgV3 trigonal pyramids,  an edgeedge with one S(1)MgV2Cr trigonal pyramid,  an edgeedge with one S(2)MgV2Cr trigonal pyramid, and  an edgeedge with one S(3)MgV3 trigonal pyramid.