MgFe2Cu6SnS8 is Aluminum carbonitride-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded to one S(1), one S(5), one S(7), and one S(8) atom to form distorted MgS4 tetrahedra that share corners with two equivalent Fe(1)S4 tetrahedra, corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra,  an edgeedge with one Fe(2)S4 tetrahedra, and  an edgeedge with one Sn(1)S4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one S(4), one S(5), one S(6), and one S(8) atom to form FeS4 tetrahedra that share corners with two equivalent Mg(1)S4 tetrahedra,  an edgeedge with one Cu(3)S4 tetrahedra,  an edgeedge with one Cu(4)S4 tetrahedra,  an edgeedge with one Cu(5)S4 tetrahedra, and edges with two equivalent Fe(2)S4 tetrahedra. In the second Fe site, Fe(2) is bonded to one S(4), one S(5), one S(6), and one S(8) atom to form distorted FeS4 tetrahedra that share corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra,  an edgeedge with one Mg(1)S4 tetrahedra, and edges with two equivalent Fe(1)S4 tetrahedra. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one S(1), one S(5), one S(7), and one S(8) atom. In the second Cu site, Cu(2) is bonded in a 3-coordinate geometry to one S(1), one S(2), one S(5), and one S(6) atom. In the third Cu site, Cu(3) is bonded to one S(2), one S(4), one S(5), and one S(7) atom to form distorted CuS4 tetrahedra that share corners with two equivalent Mg(1)S4 tetrahedra, corners with two equivalent Fe(2)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Sn(1)S4 tetrahedra, and  an edgeedge with one Fe(1)S4 tetrahedra. In the fourth Cu site, Cu(4) is bonded to one S(2), one S(3), one S(4), and one S(6) atom to form CuS4 tetrahedra that share corners with two equivalent Fe(2)S4 tetrahedra, corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra, corners with two equivalent Sn(1)S4 tetrahedra, and  an edgeedge with one Fe(1)S4 tetrahedra. In the fifth Cu site, Cu(5) is bonded to one S(1), one S(3), one S(6), and one S(8) atom to form distorted CuS4 tetrahedra that share corners with two equivalent Mg(1)S4 tetrahedra, corners with two equivalent Fe(2)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Sn(1)S4 tetrahedra, and  an edgeedge with one Fe(1)S4 tetrahedra. In the sixth Cu site, Cu(6) is bonded in a 3-coordinate geometry to one S(3), one S(4), one S(7), and one S(8) atom. Sn(1) is bonded to one S(1), one S(2), one S(3), and one S(7) atom to form distorted SnS4 tetrahedra that share corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra, and  an edgeedge with one Mg(1)S4 tetrahedra. There are eight inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one Cu(1), one Cu(2), one Cu(5), and one Sn(1) atom to form distorted SMgCu3Sn trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(7)MgCu3Sn trigonal bipyramid, corners with two equivalent S(6)Fe2Cu3 trigonal bipyramids, and  an edgeedge with one S(7)MgCu3Sn trigonal bipyramid. In the second S site, S(2) is bonded to one Cu(2), one Cu(3), one Cu(4), and one Sn(1) atom to form SCu3Sn tetrahedra that share corners with two equivalent S(3)Cu3Sn tetrahedra, corners with two equivalent S(4)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(6)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(1)MgCu3Sn trigonal bipyramids, and corners with two equivalent S(7)MgCu3Sn trigonal bipyramids. In the third S site, S(3) is bonded to one Cu(4), one Cu(5), one Cu(6), and one Sn(1) atom to form SCu3Sn tetrahedra that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(4)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(6)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(1)MgCu3Sn trigonal bipyramids, and corners with two equivalent S(7)MgCu3Sn trigonal bipyramids. In the fourth S site, S(4) is bonded to one Fe(1), one Fe(2), one Cu(3), one Cu(4), and one Cu(6) atom to form distorted SFe2Cu3 trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(6)Fe2Cu3 trigonal bipyramid, corners with two equivalent S(7)MgCu3Sn trigonal bipyramids, and  an edgeedge with one S(6)Fe2Cu3 trigonal bipyramid. In the fifth S site, S(5) is bonded in a 6-coordinate geometry to one Mg(1), one Fe(1), one Fe(2), one Cu(1), one Cu(2), and one Cu(3) atom. In the sixth S site, S(6) is bonded to one Fe(1), one Fe(2), one Cu(2), one Cu(4), and one Cu(5) atom to form distorted SFe2Cu3 trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(4)Fe2Cu3 trigonal bipyramid, corners with two equivalent S(1)MgCu3Sn trigonal bipyramids, and  an edgeedge with one S(4)Fe2Cu3 trigonal bipyramid. In the seventh S site, S(7) is bonded to one Mg(1), one Cu(1), one Cu(3), one Cu(6), and one Sn(1) atom to form distorted SMgCu3Sn trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(1)MgCu3Sn trigonal bipyramid, corners with two equivalent S(4)Fe2Cu3 trigonal bipyramids, and  an edgeedge with one S(1)MgCu3Sn trigonal bipyramid. In the eighth S site, S(8) is bonded in a 6-coordinate geometry to one Mg(1), one Fe(1), one Fe(2), one Cu(1), one Cu(5), and one Cu(6) atom.
MgFe2Cu6SnS8 is Aluminum carbonitride-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded to one S(1), one S(5), one S(7), and one S(8) atom to form distorted MgS4 tetrahedra that share corners with two equivalent Fe(1)S4 tetrahedra, corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra,  an edgeedge with one Fe(2)S4 tetrahedra, and  an edgeedge with one Sn(1)S4 tetrahedra. The Mg(1)-S(1) bond length is 2.47 Å. The Mg(1)-S(5) bond length is 2.41 Å. The Mg(1)-S(7) bond length is 2.48 Å. The Mg(1)-S(8) bond length is 2.41 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one S(4), one S(5), one S(6), and one S(8) atom to form FeS4 tetrahedra that share corners with two equivalent Mg(1)S4 tetrahedra,  an edgeedge with one Cu(3)S4 tetrahedra,  an edgeedge with one Cu(4)S4 tetrahedra,  an edgeedge with one Cu(5)S4 tetrahedra, and edges with two equivalent Fe(2)S4 tetrahedra. The Fe(1)-S(4) bond length is 2.33 Å. The Fe(1)-S(5) bond length is 2.34 Å. The Fe(1)-S(6) bond length is 2.33 Å. The Fe(1)-S(8) bond length is 2.34 Å. In the second Fe site, Fe(2) is bonded to one S(4), one S(5), one S(6), and one S(8) atom to form distorted FeS4 tetrahedra that share corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra,  an edgeedge with one Mg(1)S4 tetrahedra, and edges with two equivalent Fe(1)S4 tetrahedra. The Fe(2)-S(4) bond length is 2.32 Å. The Fe(2)-S(5) bond length is 2.41 Å. The Fe(2)-S(6) bond length is 2.32 Å. The Fe(2)-S(8) bond length is 2.41 Å. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one S(1), one S(5), one S(7), and one S(8) atom. The Cu(1)-S(1) bond length is 2.41 Å. The Cu(1)-S(5) bond length is 2.39 Å. The Cu(1)-S(7) bond length is 2.41 Å. The Cu(1)-S(8) bond length is 2.39 Å. In the second Cu site, Cu(2) is bonded in a 3-coordinate geometry to one S(1), one S(2), one S(5), and one S(6) atom. The Cu(2)-S(1) bond length is 2.28 Å. The Cu(2)-S(2) bond length is 2.25 Å. The Cu(2)-S(5) bond length is 2.94 Å. The Cu(2)-S(6) bond length is 2.25 Å. In the third Cu site, Cu(3) is bonded to one S(2), one S(4), one S(5), and one S(7) atom to form distorted CuS4 tetrahedra that share corners with two equivalent Mg(1)S4 tetrahedra, corners with two equivalent Fe(2)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Sn(1)S4 tetrahedra, and  an edgeedge with one Fe(1)S4 tetrahedra. The Cu(3)-S(2) bond length is 2.28 Å. The Cu(3)-S(4) bond length is 2.30 Å. The Cu(3)-S(5) bond length is 2.39 Å. The Cu(3)-S(7) bond length is 2.39 Å. In the fourth Cu site, Cu(4) is bonded to one S(2), one S(3), one S(4), and one S(6) atom to form CuS4 tetrahedra that share corners with two equivalent Fe(2)S4 tetrahedra, corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra, corners with two equivalent Sn(1)S4 tetrahedra, and  an edgeedge with one Fe(1)S4 tetrahedra. The Cu(4)-S(2) bond length is 2.31 Å. The Cu(4)-S(3) bond length is 2.31 Å. The Cu(4)-S(4) bond length is 2.34 Å. The Cu(4)-S(6) bond length is 2.34 Å. In the fifth Cu site, Cu(5) is bonded to one S(1), one S(3), one S(6), and one S(8) atom to form distorted CuS4 tetrahedra that share corners with two equivalent Mg(1)S4 tetrahedra, corners with two equivalent Fe(2)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Sn(1)S4 tetrahedra, and  an edgeedge with one Fe(1)S4 tetrahedra. The Cu(5)-S(1) bond length is 2.39 Å. The Cu(5)-S(3) bond length is 2.28 Å. The Cu(5)-S(6) bond length is 2.30 Å. The Cu(5)-S(8) bond length is 2.39 Å. In the sixth Cu site, Cu(6) is bonded in a 3-coordinate geometry to one S(3), one S(4), one S(7), and one S(8) atom. The Cu(6)-S(3) bond length is 2.25 Å. The Cu(6)-S(4) bond length is 2.25 Å. The Cu(6)-S(7) bond length is 2.28 Å. The Cu(6)-S(8) bond length is 2.93 Å. Sn(1) is bonded to one S(1), one S(2), one S(3), and one S(7) atom to form distorted SnS4 tetrahedra that share corners with two equivalent Cu(3)S4 tetrahedra, corners with two equivalent Cu(4)S4 tetrahedra, corners with two equivalent Cu(5)S4 tetrahedra, and  an edgeedge with one Mg(1)S4 tetrahedra. The Sn(1)-S(1) bond length is 2.57 Å. The Sn(1)-S(2) bond length is 2.45 Å. The Sn(1)-S(3) bond length is 2.45 Å. The Sn(1)-S(7) bond length is 2.57 Å. There are eight inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one Cu(1), one Cu(2), one Cu(5), and one Sn(1) atom to form distorted SMgCu3Sn trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(7)MgCu3Sn trigonal bipyramid, corners with two equivalent S(6)Fe2Cu3 trigonal bipyramids, and  an edgeedge with one S(7)MgCu3Sn trigonal bipyramid. In the second S site, S(2) is bonded to one Cu(2), one Cu(3), one Cu(4), and one Sn(1) atom to form SCu3Sn tetrahedra that share corners with two equivalent S(3)Cu3Sn tetrahedra, corners with two equivalent S(4)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(6)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(1)MgCu3Sn trigonal bipyramids, and corners with two equivalent S(7)MgCu3Sn trigonal bipyramids. In the third S site, S(3) is bonded to one Cu(4), one Cu(5), one Cu(6), and one Sn(1) atom to form SCu3Sn tetrahedra that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(4)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(6)Fe2Cu3 trigonal bipyramids, corners with two equivalent S(1)MgCu3Sn trigonal bipyramids, and corners with two equivalent S(7)MgCu3Sn trigonal bipyramids. In the fourth S site, S(4) is bonded to one Fe(1), one Fe(2), one Cu(3), one Cu(4), and one Cu(6) atom to form distorted SFe2Cu3 trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(6)Fe2Cu3 trigonal bipyramid, corners with two equivalent S(7)MgCu3Sn trigonal bipyramids, and  an edgeedge with one S(6)Fe2Cu3 trigonal bipyramid. In the fifth S site, S(5) is bonded in a 6-coordinate geometry to one Mg(1), one Fe(1), one Fe(2), one Cu(1), one Cu(2), and one Cu(3) atom. In the sixth S site, S(6) is bonded to one Fe(1), one Fe(2), one Cu(2), one Cu(4), and one Cu(5) atom to form distorted SFe2Cu3 trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(4)Fe2Cu3 trigonal bipyramid, corners with two equivalent S(1)MgCu3Sn trigonal bipyramids, and  an edgeedge with one S(4)Fe2Cu3 trigonal bipyramid. In the seventh S site, S(7) is bonded to one Mg(1), one Cu(1), one Cu(3), one Cu(6), and one Sn(1) atom to form distorted SMgCu3Sn trigonal bipyramids that share corners with two equivalent S(2)Cu3Sn tetrahedra, corners with two equivalent S(3)Cu3Sn tetrahedra,  a cornercorner with one S(1)MgCu3Sn trigonal bipyramid, corners with two equivalent S(4)Fe2Cu3 trigonal bipyramids, and  an edgeedge with one S(1)MgCu3Sn trigonal bipyramid. In the eighth S site, S(8) is bonded in a 6-coordinate geometry to one Mg(1), one Fe(1), one Fe(2), one Cu(1), one Cu(5), and one Cu(6) atom.