Tl4Bi2S5 crystallizes in the orthorhombic Pnma space group. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 4-coordinate geometry to one S(3), one S(5), and two equivalent S(1) atoms. In the second Tl site, Tl(2) is bonded in a rectangular see-saw-like geometry to one S(4) and three equivalent S(2) atoms. In the third Tl site, Tl(3) is bonded to one S(5), two equivalent S(3), and two equivalent S(4) atoms to form distorted TlS5 square pyramids that share corners with four equivalent Bi(1)S6 octahedra, edges with two equivalent Bi(1)S6 octahedra, edges with two equivalent Bi(2)S6 octahedra, and edges with two equivalent Tl(3)S5 square pyramids. The corner-sharing octahedral tilt angles range from 14-15°. In the fourth Tl site, Tl(4) is bonded in a 3-coordinate geometry to one S(3) and two equivalent S(2) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form BiS6 octahedra that share  a cornercorner with one Bi(2)S6 octahedra, corners with four equivalent Tl(3)S5 square pyramids, edges with two equivalent Bi(1)S6 octahedra, edges with two equivalent Bi(2)S6 octahedra, and edges with two equivalent Tl(3)S5 square pyramids. The corner-sharing octahedral tilt angles are 2°. In the second Bi site, Bi(2) is bonded to one S(4), two equivalent S(5), and three equivalent S(1) atoms to form BiS6 octahedra that share  a cornercorner with one Bi(1)S6 octahedra, edges with two equivalent Bi(1)S6 octahedra, edges with four equivalent Bi(2)S6 octahedra, and edges with two equivalent Tl(3)S5 square pyramids. The corner-sharing octahedral tilt angles are 2°. There are five inequivalent S sites. In the first S site, S(4) is bonded to one Tl(2), two equivalent Tl(3), one Bi(2), and two equivalent Bi(1) atoms to form distorted STl3Bi3 octahedra that share  a cornercorner with one S(1)Tl2Bi4 octahedra,  a cornercorner with one S(2)Tl5Bi octahedra, edges with two equivalent S(1)Tl2Bi4 octahedra, edges with two equivalent S(4)Tl3Bi3 octahedra, and edges with two equivalent S(2)Tl5Bi octahedra. The corner-sharing octahedral tilt angles range from 2-16°. In the second S site, S(5) is bonded in a distorted rectangular see-saw-like geometry to one Tl(1), one Tl(3), and two equivalent Bi(2) atoms. In the third S site, S(1) is bonded to two equivalent Tl(1), one Bi(1), and three equivalent Bi(2) atoms to form STl2Bi4 octahedra that share  a cornercorner with one S(4)Tl3Bi3 octahedra,  a cornercorner with one S(2)Tl5Bi octahedra, edges with two equivalent S(4)Tl3Bi3 octahedra, and edges with four equivalent S(1)Tl2Bi4 octahedra. The corner-sharing octahedral tilt angles range from 2-9°. In the fourth S site, S(2) is bonded to two equivalent Tl(4), three equivalent Tl(2), and one Bi(1) atom to form STl5Bi octahedra that share  a cornercorner with one S(1)Tl2Bi4 octahedra,  a cornercorner with one S(4)Tl3Bi3 octahedra, edges with two equivalent S(4)Tl3Bi3 octahedra, and edges with four equivalent S(2)Tl5Bi octahedra. The corner-sharing octahedral tilt angles range from 9-16°. In the fifth S site, S(3) is bonded in a 5-coordinate geometry to one Tl(1), one Tl(4), two equivalent Tl(3), and two equivalent Bi(1) atoms.
Tl4Bi2S5 crystallizes in the orthorhombic Pnma space group. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 4-coordinate geometry to one S(3), one S(5), and two equivalent S(1) atoms. The Tl(1)-S(3) bond length is 3.28 Å. The Tl(1)-S(5) bond length is 3.17 Å. Both Tl(1)-S(1) bond lengths are 2.97 Å. In the second Tl site, Tl(2) is bonded in a rectangular see-saw-like geometry to one S(4) and three equivalent S(2) atoms. The Tl(2)-S(4) bond length is 3.12 Å. There are two shorter (2.91 Å) and one longer (3.13 Å) Tl(2)-S(2) bond length. In the third Tl site, Tl(3) is bonded to one S(5), two equivalent S(3), and two equivalent S(4) atoms to form distorted TlS5 square pyramids that share corners with four equivalent Bi(1)S6 octahedra, edges with two equivalent Bi(1)S6 octahedra, edges with two equivalent Bi(2)S6 octahedra, and edges with two equivalent Tl(3)S5 square pyramids. The corner-sharing octahedral tilt angles range from 14-15°. The Tl(3)-S(5) bond length is 2.97 Å. Both Tl(3)-S(3) bond lengths are 3.13 Å. Both Tl(3)-S(4) bond lengths are 3.18 Å. In the fourth Tl site, Tl(4) is bonded in a 3-coordinate geometry to one S(3) and two equivalent S(2) atoms. The Tl(4)-S(3) bond length is 2.89 Å. Both Tl(4)-S(2) bond lengths are 3.12 Å. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form BiS6 octahedra that share  a cornercorner with one Bi(2)S6 octahedra, corners with four equivalent Tl(3)S5 square pyramids, edges with two equivalent Bi(1)S6 octahedra, edges with two equivalent Bi(2)S6 octahedra, and edges with two equivalent Tl(3)S5 square pyramids. The corner-sharing octahedral tilt angles are 2°. The Bi(1)-S(1) bond length is 3.08 Å. The Bi(1)-S(2) bond length is 2.66 Å. Both Bi(1)-S(3) bond lengths are 2.80 Å. Both Bi(1)-S(4) bond lengths are 2.86 Å. In the second Bi site, Bi(2) is bonded to one S(4), two equivalent S(5), and three equivalent S(1) atoms to form BiS6 octahedra that share  a cornercorner with one Bi(1)S6 octahedra, edges with two equivalent Bi(1)S6 octahedra, edges with four equivalent Bi(2)S6 octahedra, and edges with two equivalent Tl(3)S5 square pyramids. The corner-sharing octahedral tilt angles are 2°. The Bi(2)-S(4) bond length is 2.70 Å. Both Bi(2)-S(5) bond lengths are 2.75 Å. There are two shorter (2.97 Å) and one longer (3.00 Å) Bi(2)-S(1) bond length. There are five inequivalent S sites. In the first S site, S(4) is bonded to one Tl(2), two equivalent Tl(3), one Bi(2), and two equivalent Bi(1) atoms to form distorted STl3Bi3 octahedra that share  a cornercorner with one S(1)Tl2Bi4 octahedra,  a cornercorner with one S(2)Tl5Bi octahedra, edges with two equivalent S(1)Tl2Bi4 octahedra, edges with two equivalent S(4)Tl3Bi3 octahedra, and edges with two equivalent S(2)Tl5Bi octahedra. The corner-sharing octahedral tilt angles range from 2-16°. In the second S site, S(5) is bonded in a distorted rectangular see-saw-like geometry to one Tl(1), one Tl(3), and two equivalent Bi(2) atoms. In the third S site, S(1) is bonded to two equivalent Tl(1), one Bi(1), and three equivalent Bi(2) atoms to form STl2Bi4 octahedra that share  a cornercorner with one S(4)Tl3Bi3 octahedra,  a cornercorner with one S(2)Tl5Bi octahedra, edges with two equivalent S(4)Tl3Bi3 octahedra, and edges with four equivalent S(1)Tl2Bi4 octahedra. The corner-sharing octahedral tilt angles range from 2-9°. In the fourth S site, S(2) is bonded to two equivalent Tl(4), three equivalent Tl(2), and one Bi(1) atom to form STl5Bi octahedra that share  a cornercorner with one S(1)Tl2Bi4 octahedra,  a cornercorner with one S(4)Tl3Bi3 octahedra, edges with two equivalent S(4)Tl3Bi3 octahedra, and edges with four equivalent S(2)Tl5Bi octahedra. The corner-sharing octahedral tilt angles range from 9-16°. In the fifth S site, S(3) is bonded in a 5-coordinate geometry to one Tl(1), one Tl(4), two equivalent Tl(3), and two equivalent Bi(1) atoms.