GdSm4S5 is Caswellsilverite-like structured and crystallizes in the orthorhombic Immm space group. Gd(1) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form GdS6 octahedra that share corners with two equivalent Gd(1)S6 octahedra, corners with four equivalent Sm(2)S6 octahedra, edges with two equivalent Gd(1)S6 octahedra, edges with two equivalent Sm(2)S6 octahedra, and edges with eight equivalent Sm(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form SmS6 octahedra that share corners with two equivalent Sm(2)S6 octahedra, corners with four equivalent Sm(1)S6 octahedra, edges with three equivalent Sm(1)S6 octahedra, edges with four equivalent Gd(1)S6 octahedra, and edges with five equivalent Sm(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Sm site, Sm(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form SmS6 octahedra that share corners with two equivalent Gd(1)S6 octahedra, corners with two equivalent Sm(1)S6 octahedra, corners with two equivalent Sm(2)S6 octahedra,  an edgeedge with one Gd(1)S6 octahedra, edges with five equivalent Sm(1)S6 octahedra, and edges with six equivalent Sm(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are three inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Gd(1), two equivalent Sm(1), and two equivalent Sm(2) atoms to form SSm4Gd2 octahedra that share corners with two equivalent S(2)Sm6 octahedra, corners with four equivalent S(1)Sm4Gd2 octahedra, edges with three equivalent S(1)Sm4Gd2 octahedra, edges with four equivalent S(3)Sm4Gd2 octahedra, and edges with five equivalent S(2)Sm6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second S site, S(2) is bonded to two equivalent Sm(1) and four equivalent Sm(2) atoms to form SSm6 octahedra that share corners with two equivalent S(1)Sm4Gd2 octahedra, corners with two equivalent S(3)Sm4Gd2 octahedra, corners with two equivalent S(2)Sm6 octahedra,  an edgeedge with one S(3)Sm4Gd2 octahedra, edges with five equivalent S(1)Sm4Gd2 octahedra, and edges with six equivalent S(2)Sm6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third S site, S(3) is bonded to two equivalent Gd(1) and four equivalent Sm(1) atoms to form SSm4Gd2 octahedra that share corners with two equivalent S(3)Sm4Gd2 octahedra, corners with four equivalent S(2)Sm6 octahedra, edges with two equivalent S(3)Sm4Gd2 octahedra, edges with two equivalent S(2)Sm6 octahedra, and edges with eight equivalent S(1)Sm4Gd2 octahedra. The corner-sharing octahedra are not tilted.
GdSm4S5 is Caswellsilverite-like structured and crystallizes in the orthorhombic Immm space group. Gd(1) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form GdS6 octahedra that share corners with two equivalent Gd(1)S6 octahedra, corners with four equivalent Sm(2)S6 octahedra, edges with two equivalent Gd(1)S6 octahedra, edges with two equivalent Sm(2)S6 octahedra, and edges with eight equivalent Sm(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. Both Gd(1)-S(3) bond lengths are 2.87 Å. All Gd(1)-S(1) bond lengths are 2.88 Å. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form SmS6 octahedra that share corners with two equivalent Sm(2)S6 octahedra, corners with four equivalent Sm(1)S6 octahedra, edges with three equivalent Sm(1)S6 octahedra, edges with four equivalent Gd(1)S6 octahedra, and edges with five equivalent Sm(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. Both Sm(1)-S(1) bond lengths are 2.87 Å. Both Sm(1)-S(2) bond lengths are 2.91 Å. Both Sm(1)-S(3) bond lengths are 2.93 Å. In the second Sm site, Sm(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form SmS6 octahedra that share corners with two equivalent Gd(1)S6 octahedra, corners with two equivalent Sm(1)S6 octahedra, corners with two equivalent Sm(2)S6 octahedra,  an edgeedge with one Gd(1)S6 octahedra, edges with five equivalent Sm(1)S6 octahedra, and edges with six equivalent Sm(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. Both Sm(2)-S(1) bond lengths are 2.96 Å. There are two shorter (2.87 Å) and two longer (2.92 Å) Sm(2)-S(2) bond lengths. There are three inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Gd(1), two equivalent Sm(1), and two equivalent Sm(2) atoms to form SSm4Gd2 octahedra that share corners with two equivalent S(2)Sm6 octahedra, corners with four equivalent S(1)Sm4Gd2 octahedra, edges with three equivalent S(1)Sm4Gd2 octahedra, edges with four equivalent S(3)Sm4Gd2 octahedra, and edges with five equivalent S(2)Sm6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second S site, S(2) is bonded to two equivalent Sm(1) and four equivalent Sm(2) atoms to form SSm6 octahedra that share corners with two equivalent S(1)Sm4Gd2 octahedra, corners with two equivalent S(3)Sm4Gd2 octahedra, corners with two equivalent S(2)Sm6 octahedra,  an edgeedge with one S(3)Sm4Gd2 octahedra, edges with five equivalent S(1)Sm4Gd2 octahedra, and edges with six equivalent S(2)Sm6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third S site, S(3) is bonded to two equivalent Gd(1) and four equivalent Sm(1) atoms to form SSm4Gd2 octahedra that share corners with two equivalent S(3)Sm4Gd2 octahedra, corners with four equivalent S(2)Sm6 octahedra, edges with two equivalent S(3)Sm4Gd2 octahedra, edges with two equivalent S(2)Sm6 octahedra, and edges with eight equivalent S(1)Sm4Gd2 octahedra. The corner-sharing octahedra are not tilted.