Pb4SnS5 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one S(1), one S(2), and four equivalent S(3) atoms to form PbS6 octahedra that share  a cornercorner with one Pb(2)S6 octahedra, corners with five equivalent Pb(1)S6 octahedra, edges with four equivalent Pb(1)S6 octahedra, edges with four equivalent Pb(2)S6 octahedra, and edges with four equivalent Sn(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Pb site, Pb(2) is bonded to one S(3) and five equivalent S(2) atoms to form PbS6 octahedra that share  a cornercorner with one Pb(1)S6 octahedra,  a cornercorner with one Sn(1)S6 octahedra, corners with four equivalent Pb(2)S6 octahedra, edges with four equivalent Pb(1)S6 octahedra, and edges with eight equivalent Pb(2)S6 octahedra. The corner-sharing octahedra are not tilted. Sn(1) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form SnS6 octahedra that share corners with two equivalent Pb(2)S6 octahedra, corners with four equivalent Sn(1)S6 octahedra, edges with four equivalent Sn(1)S6 octahedra, and edges with eight equivalent Pb(1)S6 octahedra. The corner-sharing octahedra are not tilted. There are five inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Pb(1) and four equivalent Sn(1) atoms to form SSn4Pb2 octahedra that share corners with two S(2,2)Pb6 octahedra; corners with four equivalent S(1)Sn4Pb2 octahedra; edges with four equivalent S(1)Sn4Pb2 octahedra; and edges with eight equivalent S(3)SnPb5 octahedra. The corner-sharing octahedra are not tilted. In the second S site, S(2) is bonded to one Pb(1) and five equivalent Pb(2) atoms to form SPb6 octahedra that share  a cornercorner with one S(1)Sn4Pb2 octahedra,  a cornercorner with one S(3)SnPb5 octahedra, corners with four equivalent S(2)Pb6 octahedra, edges with four equivalent S(3)SnPb5 octahedra, and edges with eight equivalent S(2)Pb6 octahedra. The corner-sharing octahedra are not tilted. In the third S site, S(3) is bonded to one Pb(2), four equivalent Pb(1), and one Sn(1) atom to form SSnPb5 octahedra that share  a cornercorner with one S(2)Pb6 octahedra, corners with five equivalent S(3)SnPb5 octahedra, edges with four equivalent S(2)Pb6 octahedra, edges with four equivalent S(1)Sn4Pb2 octahedra, and edges with four equivalent S(3)SnPb5 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth S site, S(1) is bonded to two equivalent Pb(1) and four equivalent Sn(1) atoms to form SSn4Pb2 octahedra that share corners with two equivalent S(2)Pb6 octahedra, corners with four equivalent S(1)Sn4Pb2 octahedra, edges with four equivalent S(1)Sn4Pb2 octahedra, and edges with eight equivalent S(3)SnPb5 octahedra. The corner-sharing octahedra are not tilted. In the fifth S site, S(2) is bonded to one Pb(1) and five equivalent Pb(2) atoms to form SPb6 octahedra that share  a cornercorner with one S(1)Sn4Pb2 octahedra;  a cornercorner with one S(3)SnPb5 octahedra; corners with four equivalent S(2)Pb6 octahedra; edges with four equivalent S(3)SnPb5 octahedra; and edges with eight S(2,2)Pb6 octahedra. The corner-sharing octahedra are not tilted.
Pb4SnS5 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one S(1), one S(2), and four equivalent S(3) atoms to form PbS6 octahedra that share  a cornercorner with one Pb(2)S6 octahedra, corners with five equivalent Pb(1)S6 octahedra, edges with four equivalent Pb(1)S6 octahedra, edges with four equivalent Pb(2)S6 octahedra, and edges with four equivalent Sn(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. The Pb(1)-S(1) bond length is 2.99 Å. The Pb(1)-S(2) bond length is 3.03 Å. All Pb(1)-S(3) bond lengths are 2.98 Å. In the second Pb site, Pb(2) is bonded to one S(3) and five equivalent S(2) atoms to form PbS6 octahedra that share  a cornercorner with one Pb(1)S6 octahedra,  a cornercorner with one Sn(1)S6 octahedra, corners with four equivalent Pb(2)S6 octahedra, edges with four equivalent Pb(1)S6 octahedra, and edges with eight equivalent Pb(2)S6 octahedra. The corner-sharing octahedra are not tilted. The Pb(2)-S(3) bond length is 3.04 Å. There are four shorter (2.98 Å) and one longer (3.01 Å) Pb(2)-S(2) bond length. Sn(1) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form SnS6 octahedra that share corners with two equivalent Pb(2)S6 octahedra, corners with four equivalent Sn(1)S6 octahedra, edges with four equivalent Sn(1)S6 octahedra, and edges with eight equivalent Pb(1)S6 octahedra. The corner-sharing octahedra are not tilted. Both Sn(1)-S(3) bond lengths are 2.97 Å. All Sn(1)-S(1) bond lengths are 2.98 Å. There are five inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Pb(1) and four equivalent Sn(1) atoms to form SSn4Pb2 octahedra that share corners with two S(2,2)Pb6 octahedra; corners with four equivalent S(1)Sn4Pb2 octahedra; edges with four equivalent S(1)Sn4Pb2 octahedra; and edges with eight equivalent S(3)SnPb5 octahedra. The corner-sharing octahedra are not tilted. Both S(1)-Pb(1) bond lengths are 2.99 Å. In the second S site, S(2) is bonded to one Pb(1) and five equivalent Pb(2) atoms to form SPb6 octahedra that share  a cornercorner with one S(1)Sn4Pb2 octahedra,  a cornercorner with one S(3)SnPb5 octahedra, corners with four equivalent S(2)Pb6 octahedra, edges with four equivalent S(3)SnPb5 octahedra, and edges with eight equivalent S(2)Pb6 octahedra. The corner-sharing octahedra are not tilted. In the third S site, S(3) is bonded to one Pb(2), four equivalent Pb(1), and one Sn(1) atom to form SSnPb5 octahedra that share  a cornercorner with one S(2)Pb6 octahedra, corners with five equivalent S(3)SnPb5 octahedra, edges with four equivalent S(2)Pb6 octahedra, edges with four equivalent S(1)Sn4Pb2 octahedra, and edges with four equivalent S(3)SnPb5 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth S site, S(1) is bonded to two equivalent Pb(1) and four equivalent Sn(1) atoms to form SSn4Pb2 octahedra that share corners with two equivalent S(2)Pb6 octahedra, corners with four equivalent S(1)Sn4Pb2 octahedra, edges with four equivalent S(1)Sn4Pb2 octahedra, and edges with eight equivalent S(3)SnPb5 octahedra. The corner-sharing octahedra are not tilted. All S(1)-Sn(1) bond lengths are 2.98 Å. In the fifth S site, S(2) is bonded to one Pb(1) and five equivalent Pb(2) atoms to form SPb6 octahedra that share  a cornercorner with one S(1)Sn4Pb2 octahedra;  a cornercorner with one S(3)SnPb5 octahedra; corners with four equivalent S(2)Pb6 octahedra; edges with four equivalent S(3)SnPb5 octahedra; and edges with eight S(2,2)Pb6 octahedra. The corner-sharing octahedra are not tilted. The S(2)-Pb(1) bond length is 3.03 Å. There are four shorter (2.98 Å) and one longer (3.01 Å) S(2)-Pb(2) bond length.