Ba9(NdS6)2 crystallizes in the monoclinic C2/m space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form BaS6 octahedra that share  a cornercorner with one Ba(2)S6 octahedra, corners with two equivalent Ba(4)S6 octahedra, corners with two equivalent Nd(1)S6 octahedra,  an edgeedge with one Ba(2)S6 octahedra, edges with two equivalent Ba(4)S6 octahedra, edges with two equivalent Nd(1)S6 octahedra, and edges with six equivalent Ba(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 1-10°. In the second Ba site, Ba(2) is bonded to two equivalent S(2) and four equivalent S(4) atoms to form a mixture of corner and edge-sharing BaS6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third Ba site, Ba(3) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form BaS6 octahedra that share  a cornercorner with one Ba(2)S6 octahedra, corners with two equivalent Ba(4)S6 octahedra, corners with two equivalent Nd(1)S6 octahedra,  an edgeedge with one Ba(2)S6 octahedra, edges with two equivalent Ba(4)S6 octahedra, edges with two equivalent Nd(1)S6 octahedra, edges with three equivalent Ba(1)S6 octahedra, and edges with three equivalent Ba(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 1-11°. In the fourth Ba site, Ba(4) is bonded to two equivalent S(2) and four equivalent S(4) atoms to form a mixture of corner and edge-sharing BaS6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. Nd(1) is bonded to two equivalent S(1) and four equivalent S(3) atoms to form NdS6 octahedra that share corners with two equivalent Ba(1)S6 octahedra, corners with four equivalent Ba(3)S6 octahedra, edges with two equivalent Ba(1)S6 octahedra, edges with three equivalent Nd(1)S6 octahedra, and edges with four equivalent Ba(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 10-11°. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Ba(1), two equivalent Ba(3), and two equivalent Nd(1) atoms to form SBa3Nd2 square pyramids that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra, corners with six equivalent S(3)Ba3Nd2 square pyramids,  an edgeedge with one S(2)Ba6 octahedra, edges with two equivalent S(4)Ba6 octahedra,  an edgeedge with one S(1)Ba3Nd2 square pyramid, and edges with four equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. In the second S site, S(2) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), and two equivalent Ba(4) atoms to form SBa6 octahedra that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra,  a cornercorner with one S(1)Ba3Nd2 square pyramid, corners with two equivalent S(3)Ba3Nd2 square pyramids,  an edgeedge with one S(2)Ba6 octahedra, edges with eight equivalent S(4)Ba6 octahedra,  an edgeedge with one S(1)Ba3Nd2 square pyramid, and edges with two equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-1°. In the third S site, S(3) is bonded to one Ba(1), two equivalent Ba(3), and two equivalent Nd(1) atoms to form SBa3Nd2 square pyramids that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra, corners with three equivalent S(1)Ba3Nd2 square pyramids, corners with three equivalent S(3)Ba3Nd2 square pyramids,  an edgeedge with one S(2)Ba6 octahedra, edges with two equivalent S(4)Ba6 octahedra, edges with two equivalent S(1)Ba3Nd2 square pyramids, and edges with three equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. In the fourth S site, S(4) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), and two equivalent Ba(4) atoms to form SBa6 octahedra that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra,  a cornercorner with one S(1)Ba3Nd2 square pyramid, corners with two equivalent S(3)Ba3Nd2 square pyramids, edges with four equivalent S(2)Ba6 octahedra, edges with five equivalent S(4)Ba6 octahedra,  an edgeedge with one S(1)Ba3Nd2 square pyramid, and edges with two equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-1°.
Ba9(NdS6)2 crystallizes in the monoclinic C2/m space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form BaS6 octahedra that share  a cornercorner with one Ba(2)S6 octahedra, corners with two equivalent Ba(4)S6 octahedra, corners with two equivalent Nd(1)S6 octahedra,  an edgeedge with one Ba(2)S6 octahedra, edges with two equivalent Ba(4)S6 octahedra, edges with two equivalent Nd(1)S6 octahedra, and edges with six equivalent Ba(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 1-10°. The Ba(1)-S(1) bond length is 3.05 Å. The Ba(1)-S(2) bond length is 3.16 Å. Both Ba(1)-S(3) bond lengths are 3.30 Å. Both Ba(1)-S(4) bond lengths are 3.23 Å. In the second Ba site, Ba(2) is bonded to two equivalent S(2) and four equivalent S(4) atoms to form a mixture of corner and edge-sharing BaS6 octahedra. The corner-sharing octahedral tilt angles are 2°. Both Ba(2)-S(2) bond lengths are 3.17 Å. All Ba(2)-S(4) bond lengths are 3.22 Å. In the third Ba site, Ba(3) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form BaS6 octahedra that share  a cornercorner with one Ba(2)S6 octahedra, corners with two equivalent Ba(4)S6 octahedra, corners with two equivalent Nd(1)S6 octahedra,  an edgeedge with one Ba(2)S6 octahedra, edges with two equivalent Ba(4)S6 octahedra, edges with two equivalent Nd(1)S6 octahedra, edges with three equivalent Ba(1)S6 octahedra, and edges with three equivalent Ba(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 1-11°. The Ba(3)-S(1) bond length is 3.29 Å. The Ba(3)-S(2) bond length is 3.17 Å. There is one shorter (3.05 Å) and one longer (3.29 Å) Ba(3)-S(3) bond length. There is one shorter (3.23 Å) and one longer (3.25 Å) Ba(3)-S(4) bond length. In the fourth Ba site, Ba(4) is bonded to two equivalent S(2) and four equivalent S(4) atoms to form a mixture of corner and edge-sharing BaS6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. Both Ba(4)-S(2) bond lengths are 3.20 Å. There are two shorter (3.20 Å) and two longer (3.21 Å) Ba(4)-S(4) bond lengths. Nd(1) is bonded to two equivalent S(1) and four equivalent S(3) atoms to form NdS6 octahedra that share corners with two equivalent Ba(1)S6 octahedra, corners with four equivalent Ba(3)S6 octahedra, edges with two equivalent Ba(1)S6 octahedra, edges with three equivalent Nd(1)S6 octahedra, and edges with four equivalent Ba(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 10-11°. Both Nd(1)-S(1) bond lengths are 2.94 Å. There are two shorter (2.92 Å) and two longer (2.93 Å) Nd(1)-S(3) bond lengths. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Ba(1), two equivalent Ba(3), and two equivalent Nd(1) atoms to form SBa3Nd2 square pyramids that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra, corners with six equivalent S(3)Ba3Nd2 square pyramids,  an edgeedge with one S(2)Ba6 octahedra, edges with two equivalent S(4)Ba6 octahedra,  an edgeedge with one S(1)Ba3Nd2 square pyramid, and edges with four equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. In the second S site, S(2) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), and two equivalent Ba(4) atoms to form SBa6 octahedra that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra,  a cornercorner with one S(1)Ba3Nd2 square pyramid, corners with two equivalent S(3)Ba3Nd2 square pyramids,  an edgeedge with one S(2)Ba6 octahedra, edges with eight equivalent S(4)Ba6 octahedra,  an edgeedge with one S(1)Ba3Nd2 square pyramid, and edges with two equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-1°. In the third S site, S(3) is bonded to one Ba(1), two equivalent Ba(3), and two equivalent Nd(1) atoms to form SBa3Nd2 square pyramids that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra, corners with three equivalent S(1)Ba3Nd2 square pyramids, corners with three equivalent S(3)Ba3Nd2 square pyramids,  an edgeedge with one S(2)Ba6 octahedra, edges with two equivalent S(4)Ba6 octahedra, edges with two equivalent S(1)Ba3Nd2 square pyramids, and edges with three equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. In the fourth S site, S(4) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), and two equivalent Ba(4) atoms to form SBa6 octahedra that share  a cornercorner with one S(2)Ba6 octahedra, corners with two equivalent S(4)Ba6 octahedra,  a cornercorner with one S(1)Ba3Nd2 square pyramid, corners with two equivalent S(3)Ba3Nd2 square pyramids, edges with four equivalent S(2)Ba6 octahedra, edges with five equivalent S(4)Ba6 octahedra,  an edgeedge with one S(1)Ba3Nd2 square pyramid, and edges with two equivalent S(3)Ba3Nd2 square pyramids. The corner-sharing octahedral tilt angles range from 0-1°.