MgV4FeTlS8 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Tl(1), one S(1), one S(6), and two equivalent S(8) atoms. There are four inequivalent V sites. In the first V site, V(1) is bonded to one S(1), one S(7), two equivalent S(2), and two equivalent S(4) atoms to form VS6 octahedra that share corners with two equivalent V(3)S6 octahedra, corners with two equivalent V(4)S6 octahedra, corners with two equivalent Fe(1)S6 octahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and  a faceface with one V(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 49-57°. In the second V site, V(2) is bonded to one S(2), one S(8), two equivalent S(1), and two equivalent S(3) atoms to form VS6 octahedra that share corners with two equivalent V(3)S6 octahedra, corners with two equivalent V(4)S6 octahedra, corners with two equivalent Fe(1)S6 octahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and  a faceface with one V(4)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-50°. In the third V site, V(3) is bonded to one S(3), one S(7), two equivalent S(4), and two equivalent S(6) atoms to form distorted VS6 octahedra that share corners with two equivalent V(1)S6 octahedra, corners with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, edges with two equivalent V(4)S6 octahedra, edges with two equivalent Fe(1)S6 octahedra, and  a faceface with one V(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 50-53°. In the fourth V site, V(4) is bonded to one S(4), one S(8), two equivalent S(3), and two equivalent S(5) atoms to form VS6 octahedra that share corners with two equivalent V(1)S6 octahedra, corners with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, edges with two equivalent V(4)S6 octahedra, edges with two equivalent Fe(1)S6 octahedra, and  a faceface with one V(2)S6 octahedra. The corner-sharing octahedral tilt angles are 49°. Fe(1) is bonded to one S(5), one S(6), two equivalent S(7), and two equivalent S(8) atoms to form distorted FeS6 octahedra that share corners with two equivalent V(1)S6 octahedra, corners with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, edges with two equivalent V(4)S6 octahedra, and edges with two equivalent Fe(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-57°. Tl(1) is bonded in a 7-coordinate geometry to two equivalent Mg(1), one S(7), two equivalent S(2), and two equivalent S(5) atoms. There are eight inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one V(1), and two equivalent V(2) atoms. In the second S site, S(2) is bonded in a 3-coordinate geometry to one V(2), two equivalent V(1), and two equivalent Tl(1) atoms. In the third S site, S(3) is bonded to one V(3), two equivalent V(2), and two equivalent V(4) atoms to form distorted SV5 trigonal bipyramids that share corners with two equivalent S(6)MgV2Fe trigonal pyramids, edges with two equivalent S(3)V5 trigonal bipyramids, and edges with two equivalent S(4)V5 trigonal bipyramids. In the fourth S site, S(4) is bonded to one V(4), two equivalent V(1), and two equivalent V(3) atoms to form distorted SV5 trigonal bipyramids that share corners with two equivalent S(6)MgV2Fe trigonal pyramids, edges with two equivalent S(3)V5 trigonal bipyramids, edges with two equivalent S(4)V5 trigonal bipyramids, and  an edgeedge with one S(6)MgV2Fe trigonal pyramid. In the fifth S site, S(5) is bonded in a 5-coordinate geometry to two equivalent V(4), one Fe(1), and two equivalent Tl(1) atoms. In the sixth S site, S(6) is bonded to one Mg(1), two equivalent V(3), and one Fe(1) atom to form distorted SMgV2Fe trigonal pyramids that share corners with two equivalent S(3)V5 trigonal bipyramids, corners with two equivalent S(4)V5 trigonal bipyramids, corners with two equivalent S(6)MgV2Fe trigonal pyramids, and  an edgeedge with one S(4)V5 trigonal bipyramid. In the seventh S site, S(7) is bonded in a 5-coordinate geometry to one V(1), one V(3), two equivalent Fe(1), and one Tl(1) atom. In the eighth S site, S(8) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one V(2), one V(4), and two equivalent Fe(1) atoms.
MgV4FeTlS8 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Tl(1), one S(1), one S(6), and two equivalent S(8) atoms. Both Mg(1)-Tl(1) bond lengths are 3.19 Å. The Mg(1)-S(1) bond length is 2.40 Å. The Mg(1)-S(6) bond length is 2.45 Å. Both Mg(1)-S(8) bond lengths are 2.45 Å. There are four inequivalent V sites. In the first V site, V(1) is bonded to one S(1), one S(7), two equivalent S(2), and two equivalent S(4) atoms to form VS6 octahedra that share corners with two equivalent V(3)S6 octahedra, corners with two equivalent V(4)S6 octahedra, corners with two equivalent Fe(1)S6 octahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and  a faceface with one V(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 49-57°. The V(1)-S(1) bond length is 2.44 Å. The V(1)-S(7) bond length is 2.41 Å. Both V(1)-S(2) bond lengths are 2.43 Å. Both V(1)-S(4) bond lengths are 2.49 Å. In the second V site, V(2) is bonded to one S(2), one S(8), two equivalent S(1), and two equivalent S(3) atoms to form VS6 octahedra that share corners with two equivalent V(3)S6 octahedra, corners with two equivalent V(4)S6 octahedra, corners with two equivalent Fe(1)S6 octahedra, edges with two equivalent V(1)S6 octahedra, edges with two equivalent V(2)S6 octahedra, and  a faceface with one V(4)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-50°. The V(2)-S(2) bond length is 2.42 Å. The V(2)-S(8) bond length is 2.61 Å. Both V(2)-S(1) bond lengths are 2.45 Å. Both V(2)-S(3) bond lengths are 2.50 Å. In the third V site, V(3) is bonded to one S(3), one S(7), two equivalent S(4), and two equivalent S(6) atoms to form distorted VS6 octahedra that share corners with two equivalent V(1)S6 octahedra, corners with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, edges with two equivalent V(4)S6 octahedra, edges with two equivalent Fe(1)S6 octahedra, and  a faceface with one V(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 50-53°. The V(3)-S(3) bond length is 2.59 Å. The V(3)-S(7) bond length is 2.29 Å. Both V(3)-S(4) bond lengths are 2.53 Å. Both V(3)-S(6) bond lengths are 2.33 Å. In the fourth V site, V(4) is bonded to one S(4), one S(8), two equivalent S(3), and two equivalent S(5) atoms to form VS6 octahedra that share corners with two equivalent V(1)S6 octahedra, corners with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, edges with two equivalent V(4)S6 octahedra, edges with two equivalent Fe(1)S6 octahedra, and  a faceface with one V(2)S6 octahedra. The corner-sharing octahedral tilt angles are 49°. The V(4)-S(4) bond length is 2.46 Å. The V(4)-S(8) bond length is 2.42 Å. Both V(4)-S(3) bond lengths are 2.50 Å. Both V(4)-S(5) bond lengths are 2.39 Å. Fe(1) is bonded to one S(5), one S(6), two equivalent S(7), and two equivalent S(8) atoms to form distorted FeS6 octahedra that share corners with two equivalent V(1)S6 octahedra, corners with two equivalent V(2)S6 octahedra, edges with two equivalent V(3)S6 octahedra, edges with two equivalent V(4)S6 octahedra, and edges with two equivalent Fe(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-57°. The Fe(1)-S(5) bond length is 2.41 Å. The Fe(1)-S(6) bond length is 2.28 Å. Both Fe(1)-S(7) bond lengths are 2.23 Å. Both Fe(1)-S(8) bond lengths are 2.55 Å. Tl(1) is bonded in a 7-coordinate geometry to two equivalent Mg(1), one S(7), two equivalent S(2), and two equivalent S(5) atoms. The Tl(1)-S(7) bond length is 2.90 Å. Both Tl(1)-S(2) bond lengths are 3.22 Å. Both Tl(1)-S(5) bond lengths are 3.12 Å. There are eight inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one V(1), and two equivalent V(2) atoms. In the second S site, S(2) is bonded in a 3-coordinate geometry to one V(2), two equivalent V(1), and two equivalent Tl(1) atoms. In the third S site, S(3) is bonded to one V(3), two equivalent V(2), and two equivalent V(4) atoms to form distorted SV5 trigonal bipyramids that share corners with two equivalent S(6)MgV2Fe trigonal pyramids, edges with two equivalent S(3)V5 trigonal bipyramids, and edges with two equivalent S(4)V5 trigonal bipyramids. In the fourth S site, S(4) is bonded to one V(4), two equivalent V(1), and two equivalent V(3) atoms to form distorted SV5 trigonal bipyramids that share corners with two equivalent S(6)MgV2Fe trigonal pyramids, edges with two equivalent S(3)V5 trigonal bipyramids, edges with two equivalent S(4)V5 trigonal bipyramids, and  an edgeedge with one S(6)MgV2Fe trigonal pyramid. In the fifth S site, S(5) is bonded in a 5-coordinate geometry to two equivalent V(4), one Fe(1), and two equivalent Tl(1) atoms. In the sixth S site, S(6) is bonded to one Mg(1), two equivalent V(3), and one Fe(1) atom to form distorted SMgV2Fe trigonal pyramids that share corners with two equivalent S(3)V5 trigonal bipyramids, corners with two equivalent S(4)V5 trigonal bipyramids, corners with two equivalent S(6)MgV2Fe trigonal pyramids, and  an edgeedge with one S(4)V5 trigonal bipyramid. In the seventh S site, S(7) is bonded in a 5-coordinate geometry to one V(1), one V(3), two equivalent Fe(1), and one Tl(1) atom. In the eighth S site, S(8) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one V(2), one V(4), and two equivalent Fe(1) atoms.