PbIn2S4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent In sites. In the first In site, In(1) is bonded to one S(2), two equivalent S(3), and three equivalent S(1) atoms to form InS6 octahedra that share corners with four equivalent In(2)S6 octahedra, corners with six equivalent Pb(1)S7 pentagonal bipyramids, edges with four equivalent In(1)S6 octahedra,  an edgeedge with one Pb(1)S7 pentagonal bipyramid, and  a faceface with one Pb(1)S7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 49-60°. In the second In site, In(2) is bonded to one S(3), two equivalent S(2), and three equivalent S(4) atoms to form InS6 octahedra that share corners with four equivalent In(1)S6 octahedra, corners with four equivalent Pb(1)S7 pentagonal bipyramids, edges with four equivalent In(2)S6 octahedra, and edges with three equivalent Pb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 49-60°. Pb(1) is bonded to one S(2), two equivalent S(1), two equivalent S(3), and two equivalent S(4) atoms to form distorted PbS7 pentagonal bipyramids that share corners with four equivalent In(2)S6 octahedra, corners with six equivalent In(1)S6 octahedra,  an edgeedge with one In(1)S6 octahedra, edges with three equivalent In(2)S6 octahedra,  a faceface with one In(1)S6 octahedra, and faces with two equivalent Pb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 20-76°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to three equivalent In(1) and two equivalent Pb(1) atoms. In the second S site, S(2) is bonded to one In(1), two equivalent In(2), and one Pb(1) atom to form distorted SIn3Pb trigonal pyramids that share corners with six equivalent S(4)In3Pb2 square pyramids, corners with two equivalent S(2)In3Pb trigonal pyramids, and  an edgeedge with one S(4)In3Pb2 square pyramid. In the third S site, S(3) is bonded in a 5-coordinate geometry to one In(2), two equivalent In(1), and two equivalent Pb(1) atoms. In the fourth S site, S(4) is bonded to three equivalent In(2) and two equivalent Pb(1) atoms to form distorted SIn3Pb2 square pyramids that share corners with six equivalent S(2)In3Pb trigonal pyramids, edges with four equivalent S(4)In3Pb2 square pyramids, and  an edgeedge with one S(2)In3Pb trigonal pyramid.
PbIn2S4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent In sites. In the first In site, In(1) is bonded to one S(2), two equivalent S(3), and three equivalent S(1) atoms to form InS6 octahedra that share corners with four equivalent In(2)S6 octahedra, corners with six equivalent Pb(1)S7 pentagonal bipyramids, edges with four equivalent In(1)S6 octahedra,  an edgeedge with one Pb(1)S7 pentagonal bipyramid, and  a faceface with one Pb(1)S7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 49-60°. The In(1)-S(2) bond length is 2.67 Å. Both In(1)-S(3) bond lengths are 2.65 Å. There is one shorter (2.58 Å) and two longer (2.74 Å) In(1)-S(1) bond lengths. In the second In site, In(2) is bonded to one S(3), two equivalent S(2), and three equivalent S(4) atoms to form InS6 octahedra that share corners with four equivalent In(1)S6 octahedra, corners with four equivalent Pb(1)S7 pentagonal bipyramids, edges with four equivalent In(2)S6 octahedra, and edges with three equivalent Pb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 49-60°. The In(2)-S(3) bond length is 2.75 Å. Both In(2)-S(2) bond lengths are 2.62 Å. There is one shorter (2.64 Å) and two longer (2.68 Å) In(2)-S(4) bond lengths. Pb(1) is bonded to one S(2), two equivalent S(1), two equivalent S(3), and two equivalent S(4) atoms to form distorted PbS7 pentagonal bipyramids that share corners with four equivalent In(2)S6 octahedra, corners with six equivalent In(1)S6 octahedra,  an edgeedge with one In(1)S6 octahedra, edges with three equivalent In(2)S6 octahedra,  a faceface with one In(1)S6 octahedra, and faces with two equivalent Pb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 20-76°. The Pb(1)-S(2) bond length is 2.99 Å. Both Pb(1)-S(1) bond lengths are 3.03 Å. Both Pb(1)-S(3) bond lengths are 3.14 Å. Both Pb(1)-S(4) bond lengths are 3.07 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to three equivalent In(1) and two equivalent Pb(1) atoms. In the second S site, S(2) is bonded to one In(1), two equivalent In(2), and one Pb(1) atom to form distorted SIn3Pb trigonal pyramids that share corners with six equivalent S(4)In3Pb2 square pyramids, corners with two equivalent S(2)In3Pb trigonal pyramids, and  an edgeedge with one S(4)In3Pb2 square pyramid. In the third S site, S(3) is bonded in a 5-coordinate geometry to one In(2), two equivalent In(1), and two equivalent Pb(1) atoms. In the fourth S site, S(4) is bonded to three equivalent In(2) and two equivalent Pb(1) atoms to form distorted SIn3Pb2 square pyramids that share corners with six equivalent S(2)In3Pb trigonal pyramids, edges with four equivalent S(4)In3Pb2 square pyramids, and  an edgeedge with one S(2)In3Pb trigonal pyramid.