Tl2Bi2Te3Se crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to one Te(1), one Te(3), two equivalent Te(2), and two equivalent Se(1) atoms to form TlTe4Se2 octahedra that share corners with two equivalent Bi(1)Te4Se2 octahedra, corners with four equivalent Tl(1)Te4Se2 octahedra, corners with two equivalent Tl(2)Te4Se square pyramids, edges with four equivalent Bi(1)Te4Se2 octahedra, edges with four equivalent Bi(2)Te5Se octahedra, and edges with two equivalent Tl(2)Te4Se square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. In the second Tl site, Tl(2) is bonded to two equivalent Te(1), two equivalent Te(3), and one Se(1) atom to form distorted TlTe4Se square pyramids that share  a cornercorner with one Bi(2)Te5Se octahedra, corners with two equivalent Tl(1)Te4Se2 octahedra, corners with two equivalent Bi(1)Te4Se2 octahedra, corners with four equivalent Tl(2)Te4Se square pyramids, edges with two equivalent Tl(1)Te4Se2 octahedra, edges with two equivalent Bi(1)Te4Se2 octahedra, and edges with four equivalent Bi(2)Te5Se octahedra. The corner-sharing octahedral tilt angles range from 0-90°. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one Te(1), one Te(3), two equivalent Te(2), and two equivalent Se(1) atoms to form BiTe4Se2 octahedra that share corners with two equivalent Tl(1)Te4Se2 octahedra, corners with four equivalent Bi(1)Te4Se2 octahedra, corners with two equivalent Tl(2)Te4Se square pyramids, edges with four equivalent Tl(1)Te4Se2 octahedra, edges with four equivalent Bi(2)Te5Se octahedra, and edges with two equivalent Tl(2)Te4Se square pyramids. The corner-sharing octahedral tilt angles range from 0-8°. In the second Bi site, Bi(2) is bonded to one Te(2), two equivalent Te(1), two equivalent Te(3), and one Se(1) atom to form BiTe5Se octahedra that share corners with four equivalent Bi(2)Te5Se octahedra,  a cornercorner with one Tl(2)Te4Se square pyramid, edges with four equivalent Tl(1)Te4Se2 octahedra, edges with four equivalent Bi(1)Te4Se2 octahedra, and edges with four equivalent Tl(2)Te4Se square pyramids. The corner-sharing octahedral tilt angles range from 1-10°. There are three inequivalent Te sites. In the first Te site, Te(1) is bonded to one Tl(1), two equivalent Tl(2), one Bi(1), and two equivalent Bi(2) atoms to form TeTl3Bi3 octahedra that share corners with two equivalent Te(3)Tl3Bi3 octahedra, corners with four equivalent Te(1)Tl3Bi3 octahedra, edges with four equivalent Te(3)Tl3Bi3 octahedra, and edges with four equivalent Se(1)Tl3Bi3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second Te site, Te(2) is bonded in a 5-coordinate geometry to two equivalent Tl(1), one Bi(2), and two equivalent Bi(1) atoms. In the third Te site, Te(3) is bonded to one Tl(1), two equivalent Tl(2), one Bi(1), and two equivalent Bi(2) atoms to form TeTl3Bi3 octahedra that share corners with two equivalent Te(1)Tl3Bi3 octahedra, corners with four equivalent Te(3)Tl3Bi3 octahedra, edges with four equivalent Te(1)Tl3Bi3 octahedra, and edges with four equivalent Se(1)Tl3Bi3 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. Se(1) is bonded to one Tl(2), two equivalent Tl(1), one Bi(2), and two equivalent Bi(1) atoms to form SeTl3Bi3 octahedra that share corners with four equivalent Se(1)Tl3Bi3 octahedra, edges with four equivalent Te(1)Tl3Bi3 octahedra, and edges with four equivalent Te(3)Tl3Bi3 octahedra. The corner-sharing octahedral tilt angles range from 6-7°.
Tl2Bi2Te3Se crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to one Te(1), one Te(3), two equivalent Te(2), and two equivalent Se(1) atoms to form TlTe4Se2 octahedra that share corners with two equivalent Bi(1)Te4Se2 octahedra, corners with four equivalent Tl(1)Te4Se2 octahedra, corners with two equivalent Tl(2)Te4Se square pyramids, edges with four equivalent Bi(1)Te4Se2 octahedra, edges with four equivalent Bi(2)Te5Se octahedra, and edges with two equivalent Tl(2)Te4Se square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. The Tl(1)-Te(1) bond length is 3.42 Å. The Tl(1)-Te(3) bond length is 3.44 Å. Both Tl(1)-Te(2) bond lengths are 3.20 Å. Both Tl(1)-Se(1) bond lengths are 3.23 Å. In the second Tl site, Tl(2) is bonded to two equivalent Te(1), two equivalent Te(3), and one Se(1) atom to form distorted TlTe4Se square pyramids that share  a cornercorner with one Bi(2)Te5Se octahedra, corners with two equivalent Tl(1)Te4Se2 octahedra, corners with two equivalent Bi(1)Te4Se2 octahedra, corners with four equivalent Tl(2)Te4Se square pyramids, edges with two equivalent Tl(1)Te4Se2 octahedra, edges with two equivalent Bi(1)Te4Se2 octahedra, and edges with four equivalent Bi(2)Te5Se octahedra. The corner-sharing octahedral tilt angles range from 0-90°. Both Tl(2)-Te(1) bond lengths are 3.23 Å. Both Tl(2)-Te(3) bond lengths are 3.19 Å. The Tl(2)-Se(1) bond length is 3.35 Å. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one Te(1), one Te(3), two equivalent Te(2), and two equivalent Se(1) atoms to form BiTe4Se2 octahedra that share corners with two equivalent Tl(1)Te4Se2 octahedra, corners with four equivalent Bi(1)Te4Se2 octahedra, corners with two equivalent Tl(2)Te4Se square pyramids, edges with four equivalent Tl(1)Te4Se2 octahedra, edges with four equivalent Bi(2)Te5Se octahedra, and edges with two equivalent Tl(2)Te4Se square pyramids. The corner-sharing octahedral tilt angles range from 0-8°. The Bi(1)-Te(1) bond length is 3.12 Å. The Bi(1)-Te(3) bond length is 3.18 Å. Both Bi(1)-Te(2) bond lengths are 3.23 Å. Both Bi(1)-Se(1) bond lengths are 3.19 Å. In the second Bi site, Bi(2) is bonded to one Te(2), two equivalent Te(1), two equivalent Te(3), and one Se(1) atom to form BiTe5Se octahedra that share corners with four equivalent Bi(2)Te5Se octahedra,  a cornercorner with one Tl(2)Te4Se square pyramid, edges with four equivalent Tl(1)Te4Se2 octahedra, edges with four equivalent Bi(1)Te4Se2 octahedra, and edges with four equivalent Tl(2)Te4Se square pyramids. The corner-sharing octahedral tilt angles range from 1-10°. The Bi(2)-Te(2) bond length is 3.25 Å. Both Bi(2)-Te(1) bond lengths are 3.19 Å. Both Bi(2)-Te(3) bond lengths are 3.24 Å. The Bi(2)-Se(1) bond length is 2.94 Å. There are three inequivalent Te sites. In the first Te site, Te(1) is bonded to one Tl(1), two equivalent Tl(2), one Bi(1), and two equivalent Bi(2) atoms to form TeTl3Bi3 octahedra that share corners with two equivalent Te(3)Tl3Bi3 octahedra, corners with four equivalent Te(1)Tl3Bi3 octahedra, edges with four equivalent Te(3)Tl3Bi3 octahedra, and edges with four equivalent Se(1)Tl3Bi3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second Te site, Te(2) is bonded in a 5-coordinate geometry to two equivalent Tl(1), one Bi(2), and two equivalent Bi(1) atoms. In the third Te site, Te(3) is bonded to one Tl(1), two equivalent Tl(2), one Bi(1), and two equivalent Bi(2) atoms to form TeTl3Bi3 octahedra that share corners with two equivalent Te(1)Tl3Bi3 octahedra, corners with four equivalent Te(3)Tl3Bi3 octahedra, edges with four equivalent Te(1)Tl3Bi3 octahedra, and edges with four equivalent Se(1)Tl3Bi3 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. Se(1) is bonded to one Tl(2), two equivalent Tl(1), one Bi(2), and two equivalent Bi(1) atoms to form SeTl3Bi3 octahedra that share corners with four equivalent Se(1)Tl3Bi3 octahedra, edges with four equivalent Te(1)Tl3Bi3 octahedra, and edges with four equivalent Te(3)Tl3Bi3 octahedra. The corner-sharing octahedral tilt angles range from 6-7°.