MgYb2S4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a rectangular see-saw-like geometry to one S(2), one S(3), and two equivalent S(1) atoms. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form distorted YbS6 octahedra that share corners with two equivalent Yb(2)S7 pentagonal bipyramids, edges with two equivalent Yb(1)S6 octahedra, and edges with four equivalent Yb(2)S7 pentagonal bipyramids. In the second Yb site, Yb(2) is bonded to one S(2), two equivalent S(3), and four equivalent S(1) atoms to form distorted YbS7 pentagonal bipyramids that share corners with two equivalent Yb(1)S6 octahedra, corners with six equivalent Yb(2)S7 pentagonal bipyramids, and edges with four equivalent Yb(1)S6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Mg(1), one Yb(1), and two equivalent Yb(2) atoms. In the second S site, S(2) is bonded to one Mg(1), one Yb(2), and two equivalent Yb(1) atoms to form SYb3Mg trigonal pyramids that share corners with three equivalent S(3)Yb4Mg trigonal bipyramids, corners with two equivalent S(2)Yb3Mg trigonal pyramids, and edges with two equivalent S(3)Yb4Mg trigonal bipyramids. In the third S site, S(3) is bonded to one Mg(1), two equivalent Yb(1), and two equivalent Yb(2) atoms to form SYb4Mg trigonal bipyramids that share corners with four equivalent S(3)Yb4Mg trigonal bipyramids, corners with three equivalent S(2)Yb3Mg trigonal pyramids, and edges with two equivalent S(2)Yb3Mg trigonal pyramids.
MgYb2S4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a rectangular see-saw-like geometry to one S(2), one S(3), and two equivalent S(1) atoms. The Mg(1)-S(2) bond length is 2.49 Å. The Mg(1)-S(3) bond length is 2.41 Å. Both Mg(1)-S(1) bond lengths are 2.41 Å. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form distorted YbS6 octahedra that share corners with two equivalent Yb(2)S7 pentagonal bipyramids, edges with two equivalent Yb(1)S6 octahedra, and edges with four equivalent Yb(2)S7 pentagonal bipyramids. Both Yb(1)-S(1) bond lengths are 2.84 Å. Both Yb(1)-S(2) bond lengths are 2.86 Å. Both Yb(1)-S(3) bond lengths are 2.79 Å. In the second Yb site, Yb(2) is bonded to one S(2), two equivalent S(3), and four equivalent S(1) atoms to form distorted YbS7 pentagonal bipyramids that share corners with two equivalent Yb(1)S6 octahedra, corners with six equivalent Yb(2)S7 pentagonal bipyramids, and edges with four equivalent Yb(1)S6 octahedra. The corner-sharing octahedral tilt angles are 50°. The Yb(2)-S(2) bond length is 2.78 Å. There is one shorter (2.87 Å) and one longer (2.96 Å) Yb(2)-S(3) bond length. There are two shorter (2.88 Å) and two longer (2.99 Å) Yb(2)-S(1) bond lengths. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Mg(1), one Yb(1), and two equivalent Yb(2) atoms. In the second S site, S(2) is bonded to one Mg(1), one Yb(2), and two equivalent Yb(1) atoms to form SYb3Mg trigonal pyramids that share corners with three equivalent S(3)Yb4Mg trigonal bipyramids, corners with two equivalent S(2)Yb3Mg trigonal pyramids, and edges with two equivalent S(3)Yb4Mg trigonal bipyramids. In the third S site, S(3) is bonded to one Mg(1), two equivalent Yb(1), and two equivalent Yb(2) atoms to form SYb4Mg trigonal bipyramids that share corners with four equivalent S(3)Yb4Mg trigonal bipyramids, corners with three equivalent S(2)Yb3Mg trigonal pyramids, and edges with two equivalent S(2)Yb3Mg trigonal pyramids.