Gd3InS6 crystallizes in the orthorhombic Pnnm space group. There are three inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to one S(2), one S(5), two equivalent S(1), two equivalent S(3), and two equivalent S(6) atoms. In the second Gd site, Gd(2) is bonded to one S(1), one S(3), one S(5), two equivalent S(4), and two equivalent S(6) atoms to form distorted GdS7 pentagonal bipyramids that share  a cornercorner with one In(2)S6 octahedra, edges with two equivalent In(1)S6 octahedra, and edges with two equivalent Gd(2)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 41°. In the third Gd site, Gd(3) is bonded in a 8-coordinate geometry to one S(5), one S(6), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. There are two inequivalent In sites. In the first In site, In(1) is bonded to two equivalent S(4) and four equivalent S(5) atoms to form InS6 octahedra that share edges with two equivalent In(1)S6 octahedra and edges with four equivalent Gd(2)S7 pentagonal bipyramids. In the second In site, In(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form InS6 octahedra that share corners with two equivalent Gd(2)S7 pentagonal bipyramids and edges with two equivalent In(2)S6 octahedra. There are six inequivalent S sites. In the first S site, S(5) is bonded to one Gd(1), one Gd(2), one Gd(3), and two equivalent In(1) atoms to form distorted SGd3In2 trigonal bipyramids that share  a cornercorner with one S(3)Gd5 trigonal bipyramid,  a cornercorner with one S(6)Gd5 trigonal bipyramid, corners with three equivalent S(2)Gd3In2 trigonal bipyramids, corners with four equivalent S(5)Gd3In2 trigonal bipyramids, corners with three equivalent S(1)Gd3In trigonal pyramids, edges with four equivalent S(4)Gd4In square pyramids,  an edgeedge with one S(5)Gd3In2 trigonal bipyramid, edges with two equivalent S(3)Gd5 trigonal bipyramids, and edges with two equivalent S(6)Gd5 trigonal bipyramids. In the second S site, S(6) is bonded to one Gd(3), two equivalent Gd(1), and two equivalent Gd(2) atoms to form distorted SGd5 trigonal bipyramids that share corners with four equivalent S(4)Gd4In square pyramids,  a cornercorner with one S(5)Gd3In2 trigonal bipyramid, corners with two equivalent S(3)Gd5 trigonal bipyramids, corners with four equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(4)Gd4In square pyramid, edges with two equivalent S(2)Gd3In2 trigonal bipyramids, edges with two equivalent S(5)Gd3In2 trigonal bipyramids, edges with two equivalent S(6)Gd5 trigonal bipyramids, edges with three equivalent S(3)Gd5 trigonal bipyramids, and  an edgeedge with one S(1)Gd3In trigonal pyramid. In the third S site, S(1) is bonded to one Gd(2), two equivalent Gd(1), and one In(2) atom to form distorted SGd3In trigonal pyramids that share corners with two equivalent S(4)Gd4In square pyramids, corners with two equivalent S(2)Gd3In2 trigonal bipyramids, corners with two equivalent S(3)Gd5 trigonal bipyramids, corners with three equivalent S(5)Gd3In2 trigonal bipyramids, corners with four equivalent S(6)Gd5 trigonal bipyramids, corners with three equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(6)Gd5 trigonal bipyramid, edges with two equivalent S(2)Gd3In2 trigonal bipyramids, and  a faceface with one S(3)Gd5 trigonal bipyramid. In the fourth S site, S(2) is bonded to one Gd(1), two equivalent Gd(3), and two equivalent In(2) atoms to form SGd3In2 trigonal bipyramids that share corners with two equivalent S(4)Gd4In square pyramids, corners with two equivalent S(2)Gd3In2 trigonal bipyramids, corners with three equivalent S(5)Gd3In2 trigonal bipyramids, corners with four equivalent S(3)Gd5 trigonal bipyramids, corners with two equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(4)Gd4In square pyramid,  an edgeedge with one S(3)Gd5 trigonal bipyramid, edges with two equivalent S(6)Gd5 trigonal bipyramids, edges with three equivalent S(2)Gd3In2 trigonal bipyramids, and edges with two equivalent S(1)Gd3In trigonal pyramids. In the fifth S site, S(3) is bonded to one Gd(2), two equivalent Gd(1), and two equivalent Gd(3) atoms to form distorted SGd5 trigonal bipyramids that share corners with four equivalent S(4)Gd4In square pyramids,  a cornercorner with one S(5)Gd3In2 trigonal bipyramid, corners with two equivalent S(6)Gd5 trigonal bipyramids, corners with four equivalent S(2)Gd3In2 trigonal bipyramids, corners with two equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(4)Gd4In square pyramid,  an edgeedge with one S(2)Gd3In2 trigonal bipyramid, edges with two equivalent S(5)Gd3In2 trigonal bipyramids, edges with two equivalent S(3)Gd5 trigonal bipyramids, edges with three equivalent S(6)Gd5 trigonal bipyramids, and  a faceface with one S(1)Gd3In trigonal pyramid. In the sixth S site, S(4) is bonded to two equivalent Gd(2), two equivalent Gd(3), and one In(1) atom to form SGd4In square pyramids that share  a cornercorner with one S(4)Gd4In square pyramid, corners with two equivalent S(2)Gd3In2 trigonal bipyramids, corners with four equivalent S(3)Gd5 trigonal bipyramids, corners with four equivalent S(6)Gd5 trigonal bipyramids, corners with two equivalent S(1)Gd3In trigonal pyramids, edges with two equivalent S(4)Gd4In square pyramids,  an edgeedge with one S(2)Gd3In2 trigonal bipyramid,  an edgeedge with one S(3)Gd5 trigonal bipyramid,  an edgeedge with one S(6)Gd5 trigonal bipyramid, and edges with four equivalent S(5)Gd3In2 trigonal bipyramids.
Gd3InS6 crystallizes in the orthorhombic Pnnm space group. There are three inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to one S(2), one S(5), two equivalent S(1), two equivalent S(3), and two equivalent S(6) atoms. The Gd(1)-S(2) bond length is 2.94 Å. The Gd(1)-S(5) bond length is 2.87 Å. Both Gd(1)-S(1) bond lengths are 2.81 Å. Both Gd(1)-S(3) bond lengths are 2.94 Å. Both Gd(1)-S(6) bond lengths are 2.87 Å. In the second Gd site, Gd(2) is bonded to one S(1), one S(3), one S(5), two equivalent S(4), and two equivalent S(6) atoms to form distorted GdS7 pentagonal bipyramids that share  a cornercorner with one In(2)S6 octahedra, edges with two equivalent In(1)S6 octahedra, and edges with two equivalent Gd(2)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 41°. The Gd(2)-S(1) bond length is 2.75 Å. The Gd(2)-S(3) bond length is 2.92 Å. The Gd(2)-S(5) bond length is 2.93 Å. Both Gd(2)-S(4) bond lengths are 2.84 Å. Both Gd(2)-S(6) bond lengths are 2.77 Å. In the third Gd site, Gd(3) is bonded in a 8-coordinate geometry to one S(5), one S(6), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. The Gd(3)-S(5) bond length is 3.14 Å. The Gd(3)-S(6) bond length is 3.07 Å. Both Gd(3)-S(2) bond lengths are 2.87 Å. Both Gd(3)-S(3) bond lengths are 2.79 Å. Both Gd(3)-S(4) bond lengths are 2.98 Å. There are two inequivalent In sites. In the first In site, In(1) is bonded to two equivalent S(4) and four equivalent S(5) atoms to form InS6 octahedra that share edges with two equivalent In(1)S6 octahedra and edges with four equivalent Gd(2)S7 pentagonal bipyramids. Both In(1)-S(4) bond lengths are 2.62 Å. All In(1)-S(5) bond lengths are 2.61 Å. In the second In site, In(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form InS6 octahedra that share corners with two equivalent Gd(2)S7 pentagonal bipyramids and edges with two equivalent In(2)S6 octahedra. Both In(2)-S(1) bond lengths are 2.46 Å. All In(2)-S(2) bond lengths are 2.73 Å. There are six inequivalent S sites. In the first S site, S(5) is bonded to one Gd(1), one Gd(2), one Gd(3), and two equivalent In(1) atoms to form distorted SGd3In2 trigonal bipyramids that share  a cornercorner with one S(3)Gd5 trigonal bipyramid,  a cornercorner with one S(6)Gd5 trigonal bipyramid, corners with three equivalent S(2)Gd3In2 trigonal bipyramids, corners with four equivalent S(5)Gd3In2 trigonal bipyramids, corners with three equivalent S(1)Gd3In trigonal pyramids, edges with four equivalent S(4)Gd4In square pyramids,  an edgeedge with one S(5)Gd3In2 trigonal bipyramid, edges with two equivalent S(3)Gd5 trigonal bipyramids, and edges with two equivalent S(6)Gd5 trigonal bipyramids. In the second S site, S(6) is bonded to one Gd(3), two equivalent Gd(1), and two equivalent Gd(2) atoms to form distorted SGd5 trigonal bipyramids that share corners with four equivalent S(4)Gd4In square pyramids,  a cornercorner with one S(5)Gd3In2 trigonal bipyramid, corners with two equivalent S(3)Gd5 trigonal bipyramids, corners with four equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(4)Gd4In square pyramid, edges with two equivalent S(2)Gd3In2 trigonal bipyramids, edges with two equivalent S(5)Gd3In2 trigonal bipyramids, edges with two equivalent S(6)Gd5 trigonal bipyramids, edges with three equivalent S(3)Gd5 trigonal bipyramids, and  an edgeedge with one S(1)Gd3In trigonal pyramid. In the third S site, S(1) is bonded to one Gd(2), two equivalent Gd(1), and one In(2) atom to form distorted SGd3In trigonal pyramids that share corners with two equivalent S(4)Gd4In square pyramids, corners with two equivalent S(2)Gd3In2 trigonal bipyramids, corners with two equivalent S(3)Gd5 trigonal bipyramids, corners with three equivalent S(5)Gd3In2 trigonal bipyramids, corners with four equivalent S(6)Gd5 trigonal bipyramids, corners with three equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(6)Gd5 trigonal bipyramid, edges with two equivalent S(2)Gd3In2 trigonal bipyramids, and  a faceface with one S(3)Gd5 trigonal bipyramid. In the fourth S site, S(2) is bonded to one Gd(1), two equivalent Gd(3), and two equivalent In(2) atoms to form SGd3In2 trigonal bipyramids that share corners with two equivalent S(4)Gd4In square pyramids, corners with two equivalent S(2)Gd3In2 trigonal bipyramids, corners with three equivalent S(5)Gd3In2 trigonal bipyramids, corners with four equivalent S(3)Gd5 trigonal bipyramids, corners with two equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(4)Gd4In square pyramid,  an edgeedge with one S(3)Gd5 trigonal bipyramid, edges with two equivalent S(6)Gd5 trigonal bipyramids, edges with three equivalent S(2)Gd3In2 trigonal bipyramids, and edges with two equivalent S(1)Gd3In trigonal pyramids. In the fifth S site, S(3) is bonded to one Gd(2), two equivalent Gd(1), and two equivalent Gd(3) atoms to form distorted SGd5 trigonal bipyramids that share corners with four equivalent S(4)Gd4In square pyramids,  a cornercorner with one S(5)Gd3In2 trigonal bipyramid, corners with two equivalent S(6)Gd5 trigonal bipyramids, corners with four equivalent S(2)Gd3In2 trigonal bipyramids, corners with two equivalent S(1)Gd3In trigonal pyramids,  an edgeedge with one S(4)Gd4In square pyramid,  an edgeedge with one S(2)Gd3In2 trigonal bipyramid, edges with two equivalent S(5)Gd3In2 trigonal bipyramids, edges with two equivalent S(3)Gd5 trigonal bipyramids, edges with three equivalent S(6)Gd5 trigonal bipyramids, and  a faceface with one S(1)Gd3In trigonal pyramid. In the sixth S site, S(4) is bonded to two equivalent Gd(2), two equivalent Gd(3), and one In(1) atom to form SGd4In square pyramids that share  a cornercorner with one S(4)Gd4In square pyramid, corners with two equivalent S(2)Gd3In2 trigonal bipyramids, corners with four equivalent S(3)Gd5 trigonal bipyramids, corners with four equivalent S(6)Gd5 trigonal bipyramids, corners with two equivalent S(1)Gd3In trigonal pyramids, edges with two equivalent S(4)Gd4In square pyramids,  an edgeedge with one S(2)Gd3In2 trigonal bipyramid,  an edgeedge with one S(3)Gd5 trigonal bipyramid,  an edgeedge with one S(6)Gd5 trigonal bipyramid, and edges with four equivalent S(5)Gd3In2 trigonal bipyramids.