ThNd2S5 crystallizes in the orthorhombic Pnma space group. Th(1) is bonded to one S(2), one S(3), one S(4), and four equivalent S(1) atoms to form distorted edge-sharing ThS7 pentagonal bipyramids. Nd(1) is bonded in a 8-coordinate geometry to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Th(1) and two equivalent Nd(1) atoms to form distorted SNd2Th2 trigonal pyramids that share corners with two equivalent S(4)Nd4Th square pyramids, corners with four equivalent S(3)Nd4Th square pyramids, corners with two equivalent S(2)Nd4Th trigonal bipyramids, corners with six equivalent S(1)Nd2Th2 trigonal pyramids,  an edgeedge with one S(3)Nd4Th square pyramid, edges with two equivalent S(4)Nd4Th square pyramids, edges with two equivalent S(2)Nd4Th trigonal bipyramids, and  an edgeedge with one S(1)Nd2Th2 trigonal pyramid. In the second S site, S(2) is bonded to one Th(1) and four equivalent Nd(1) atoms to form distorted SNd4Th trigonal bipyramids that share  a cornercorner with one S(4)Nd4Th square pyramid, corners with five equivalent S(3)Nd4Th square pyramids, corners with four equivalent S(2)Nd4Th trigonal bipyramids, corners with four equivalent S(1)Nd2Th2 trigonal pyramids, edges with two equivalent S(3)Nd4Th square pyramids, edges with four equivalent S(4)Nd4Th square pyramids, and edges with four equivalent S(1)Nd2Th2 trigonal pyramids. In the third S site, S(3) is bonded to one Th(1) and four equivalent Nd(1) atoms to form SNd4Th square pyramids that share corners with four equivalent S(4)Nd4Th square pyramids, corners with five equivalent S(2)Nd4Th trigonal bipyramids, corners with eight equivalent S(1)Nd2Th2 trigonal pyramids,  an edgeedge with one S(4)Nd4Th square pyramid, edges with two equivalent S(3)Nd4Th square pyramids, edges with two equivalent S(2)Nd4Th trigonal bipyramids, edges with two equivalent S(1)Nd2Th2 trigonal pyramids, and  a faceface with one S(4)Nd4Th square pyramid. In the fourth S site, S(4) is bonded to one Th(1) and four equivalent Nd(1) atoms to form distorted SNd4Th square pyramids that share corners with four equivalent S(3)Nd4Th square pyramids, corners with four equivalent S(4)Nd4Th square pyramids,  a cornercorner with one S(2)Nd4Th trigonal bipyramid, corners with four equivalent S(1)Nd2Th2 trigonal pyramids,  an edgeedge with one S(3)Nd4Th square pyramid, edges with four equivalent S(2)Nd4Th trigonal bipyramids, edges with four equivalent S(1)Nd2Th2 trigonal pyramids, and  a faceface with one S(3)Nd4Th square pyramid.
ThNd2S5 crystallizes in the orthorhombic Pnma space group. Th(1) is bonded to one S(2), one S(3), one S(4), and four equivalent S(1) atoms to form distorted edge-sharing ThS7 pentagonal bipyramids. The Th(1)-S(2) bond length is 2.85 Å. The Th(1)-S(3) bond length is 2.91 Å. The Th(1)-S(4) bond length is 2.89 Å. There are two shorter (2.73 Å) and two longer (2.81 Å) Th(1)-S(1) bond lengths. Nd(1) is bonded in a 8-coordinate geometry to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. There is one shorter (2.88 Å) and one longer (2.91 Å) Nd(1)-S(1) bond length. There is one shorter (3.00 Å) and one longer (3.13 Å) Nd(1)-S(2) bond length. There is one shorter (2.99 Å) and one longer (3.01 Å) Nd(1)-S(3) bond length. There is one shorter (2.94 Å) and one longer (3.00 Å) Nd(1)-S(4) bond length. There are four inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Th(1) and two equivalent Nd(1) atoms to form distorted SNd2Th2 trigonal pyramids that share corners with two equivalent S(4)Nd4Th square pyramids, corners with four equivalent S(3)Nd4Th square pyramids, corners with two equivalent S(2)Nd4Th trigonal bipyramids, corners with six equivalent S(1)Nd2Th2 trigonal pyramids,  an edgeedge with one S(3)Nd4Th square pyramid, edges with two equivalent S(4)Nd4Th square pyramids, edges with two equivalent S(2)Nd4Th trigonal bipyramids, and  an edgeedge with one S(1)Nd2Th2 trigonal pyramid. In the second S site, S(2) is bonded to one Th(1) and four equivalent Nd(1) atoms to form distorted SNd4Th trigonal bipyramids that share  a cornercorner with one S(4)Nd4Th square pyramid, corners with five equivalent S(3)Nd4Th square pyramids, corners with four equivalent S(2)Nd4Th trigonal bipyramids, corners with four equivalent S(1)Nd2Th2 trigonal pyramids, edges with two equivalent S(3)Nd4Th square pyramids, edges with four equivalent S(4)Nd4Th square pyramids, and edges with four equivalent S(1)Nd2Th2 trigonal pyramids. In the third S site, S(3) is bonded to one Th(1) and four equivalent Nd(1) atoms to form SNd4Th square pyramids that share corners with four equivalent S(4)Nd4Th square pyramids, corners with five equivalent S(2)Nd4Th trigonal bipyramids, corners with eight equivalent S(1)Nd2Th2 trigonal pyramids,  an edgeedge with one S(4)Nd4Th square pyramid, edges with two equivalent S(3)Nd4Th square pyramids, edges with two equivalent S(2)Nd4Th trigonal bipyramids, edges with two equivalent S(1)Nd2Th2 trigonal pyramids, and  a faceface with one S(4)Nd4Th square pyramid. In the fourth S site, S(4) is bonded to one Th(1) and four equivalent Nd(1) atoms to form distorted SNd4Th square pyramids that share corners with four equivalent S(3)Nd4Th square pyramids, corners with four equivalent S(4)Nd4Th square pyramids,  a cornercorner with one S(2)Nd4Th trigonal bipyramid, corners with four equivalent S(1)Nd2Th2 trigonal pyramids,  an edgeedge with one S(3)Nd4Th square pyramid, edges with four equivalent S(2)Nd4Th trigonal bipyramids, edges with four equivalent S(1)Nd2Th2 trigonal pyramids, and  a faceface with one S(3)Nd4Th square pyramid.