Yb3NdS6 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one S(2), two equivalent S(6), and three equivalent S(1) atoms. In the second Yb site, Yb(2) is bonded to one S(1), two equivalent S(5), and three equivalent S(3) atoms to form YbS6 octahedra that share corners with three equivalent Yb(3)S5 square pyramids and edges with four equivalent Yb(2)S6 octahedra. In the third Yb site, Yb(3) is bonded to one S(3), two equivalent S(2), and two equivalent S(4) atoms to form distorted YbS5 square pyramids that share corners with three equivalent Yb(2)S6 octahedra and edges with two equivalent Yb(3)S5 square pyramids. The corner-sharing octahedral tilt angles range from 55-71°. Nd(1) is bonded in a 8-coordinate geometry to one S(2), two equivalent S(4), two equivalent S(5), and three equivalent S(6) atoms. There are six inequivalent S sites. In the first S site, S(1) is bonded to one Yb(2) and three equivalent Yb(1) atoms to form SYb4 tetrahedra that share corners with two equivalent S(1)Yb4 tetrahedra, corners with three equivalent S(2)Yb3Nd tetrahedra, corners with four equivalent S(6)Yb2Nd3 trigonal bipyramids, corners with three equivalent S(3)Yb4 trigonal pyramids, edges with two equivalent S(1)Yb4 tetrahedra, and  an edgeedge with one S(6)Yb2Nd3 trigonal bipyramid. In the second S site, S(2) is bonded to one Yb(1), two equivalent Yb(3), and one Nd(1) atom to form distorted SYb3Nd tetrahedra that share corners with two equivalent S(2)Yb3Nd tetrahedra, corners with three equivalent S(1)Yb4 tetrahedra,  a cornercorner with one S(6)Yb2Nd3 trigonal bipyramid, corners with two equivalent S(3)Yb4 trigonal pyramids, and edges with two equivalent S(6)Yb2Nd3 trigonal bipyramids. In the third S site, S(3) is bonded to one Yb(3) and three equivalent Yb(2) atoms to form SYb4 trigonal pyramids that share corners with two equivalent S(2)Yb3Nd tetrahedra, corners with three equivalent S(1)Yb4 tetrahedra, corners with two equivalent S(3)Yb4 trigonal pyramids, and edges with two equivalent S(3)Yb4 trigonal pyramids. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to two equivalent Yb(3), two equivalent Nd(1), and one S(5) atom. In the fifth S site, S(5) is bonded in a 5-coordinate geometry to two equivalent Yb(2), two equivalent Nd(1), and one S(4) atom. In the sixth S site, S(6) is bonded to two equivalent Yb(1) and three equivalent Nd(1) atoms to form distorted SYb2Nd3 trigonal bipyramids that share  a cornercorner with one S(2)Yb3Nd tetrahedra, corners with four equivalent S(1)Yb4 tetrahedra,  an edgeedge with one S(1)Yb4 tetrahedra, edges with two equivalent S(2)Yb3Nd tetrahedra, and edges with four equivalent S(6)Yb2Nd3 trigonal bipyramids.
Yb3NdS6 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one S(2), two equivalent S(6), and three equivalent S(1) atoms. The Yb(1)-S(2) bond length is 2.70 Å. Both Yb(1)-S(6) bond lengths are 2.92 Å. There is one shorter (2.87 Å) and two longer (2.92 Å) Yb(1)-S(1) bond lengths. In the second Yb site, Yb(2) is bonded to one S(1), two equivalent S(5), and three equivalent S(3) atoms to form YbS6 octahedra that share corners with three equivalent Yb(3)S5 square pyramids and edges with four equivalent Yb(2)S6 octahedra. The Yb(2)-S(1) bond length is 3.09 Å. Both Yb(2)-S(5) bond lengths are 3.05 Å. There are two shorter (2.66 Å) and one longer (2.75 Å) Yb(2)-S(3) bond length. In the third Yb site, Yb(3) is bonded to one S(3), two equivalent S(2), and two equivalent S(4) atoms to form distorted YbS5 square pyramids that share corners with three equivalent Yb(2)S6 octahedra and edges with two equivalent Yb(3)S5 square pyramids. The corner-sharing octahedral tilt angles range from 55-71°. The Yb(3)-S(3) bond length is 2.59 Å. Both Yb(3)-S(2) bond lengths are 2.67 Å. Both Yb(3)-S(4) bond lengths are 2.97 Å. Nd(1) is bonded in a 8-coordinate geometry to one S(2), two equivalent S(4), two equivalent S(5), and three equivalent S(6) atoms. The Nd(1)-S(2) bond length is 2.85 Å. Both Nd(1)-S(4) bond lengths are 2.94 Å. Both Nd(1)-S(5) bond lengths are 3.03 Å. There is one shorter (2.86 Å) and two longer (2.88 Å) Nd(1)-S(6) bond lengths. There are six inequivalent S sites. In the first S site, S(1) is bonded to one Yb(2) and three equivalent Yb(1) atoms to form SYb4 tetrahedra that share corners with two equivalent S(1)Yb4 tetrahedra, corners with three equivalent S(2)Yb3Nd tetrahedra, corners with four equivalent S(6)Yb2Nd3 trigonal bipyramids, corners with three equivalent S(3)Yb4 trigonal pyramids, edges with two equivalent S(1)Yb4 tetrahedra, and  an edgeedge with one S(6)Yb2Nd3 trigonal bipyramid. In the second S site, S(2) is bonded to one Yb(1), two equivalent Yb(3), and one Nd(1) atom to form distorted SYb3Nd tetrahedra that share corners with two equivalent S(2)Yb3Nd tetrahedra, corners with three equivalent S(1)Yb4 tetrahedra,  a cornercorner with one S(6)Yb2Nd3 trigonal bipyramid, corners with two equivalent S(3)Yb4 trigonal pyramids, and edges with two equivalent S(6)Yb2Nd3 trigonal bipyramids. In the third S site, S(3) is bonded to one Yb(3) and three equivalent Yb(2) atoms to form SYb4 trigonal pyramids that share corners with two equivalent S(2)Yb3Nd tetrahedra, corners with three equivalent S(1)Yb4 tetrahedra, corners with two equivalent S(3)Yb4 trigonal pyramids, and edges with two equivalent S(3)Yb4 trigonal pyramids. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to two equivalent Yb(3), two equivalent Nd(1), and one S(5) atom. The S(4)-S(5) bond length is 2.11 Å. In the fifth S site, S(5) is bonded in a 5-coordinate geometry to two equivalent Yb(2), two equivalent Nd(1), and one S(4) atom. In the sixth S site, S(6) is bonded to two equivalent Yb(1) and three equivalent Nd(1) atoms to form distorted SYb2Nd3 trigonal bipyramids that share  a cornercorner with one S(2)Yb3Nd tetrahedra, corners with four equivalent S(1)Yb4 tetrahedra,  an edgeedge with one S(1)Yb4 tetrahedra, edges with two equivalent S(2)Yb3Nd tetrahedra, and edges with four equivalent S(6)Yb2Nd3 trigonal bipyramids.