TlTlAl2Se4 crystallizes in the monoclinic C2/c space group. The structure consists of eight 7440-28-0 atoms inside a TlAl2Se4 framework. In the TlAl2Se4 framework, Tl(2) is bonded in a 6-coordinate geometry to one Se(1), one Se(3), one Se(4), one Se(5), and two equivalent Se(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(5) atom to form corner-sharing AlSe4 tetrahedra. In the second Al site, Al(2) is bonded to one Se(1), one Se(2), one Se(4), and one Se(5) atom to form corner-sharing AlSe4 tetrahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a water-like geometry to one Tl(2), one Al(1), and one Al(2) atom. In the second Se site, Se(2) is bonded in a water-like geometry to two equivalent Tl(2), one Al(1), and one Al(2) atom. In the third Se site, Se(3) is bonded in a water-like geometry to two equivalent Tl(2) and two equivalent Al(1) atoms. In the fourth Se site, Se(4) is bonded in a water-like geometry to two equivalent Tl(2) and two equivalent Al(2) atoms. In the fifth Se site, Se(5) is bonded in a water-like geometry to one Tl(2), one Al(1), and one Al(2) atom.
TlTlAl2Se4 crystallizes in the monoclinic C2/c space group. The structure consists of eight 7440-28-0 atoms inside a TlAl2Se4 framework. In the TlAl2Se4 framework, Tl(2) is bonded in a 6-coordinate geometry to one Se(1), one Se(3), one Se(4), one Se(5), and two equivalent Se(2) atoms. The Tl(2)-Se(1) bond length is 3.36 Å. The Tl(2)-Se(3) bond length is 3.41 Å. The Tl(2)-Se(4) bond length is 3.42 Å. The Tl(2)-Se(5) bond length is 3.39 Å. There is one shorter (3.40 Å) and one longer (3.42 Å) Tl(2)-Se(2) bond length. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(5) atom to form corner-sharing AlSe4 tetrahedra. The Al(1)-Se(1) bond length is 2.39 Å. The Al(1)-Se(2) bond length is 2.39 Å. The Al(1)-Se(3) bond length is 2.39 Å. The Al(1)-Se(5) bond length is 2.39 Å. In the second Al site, Al(2) is bonded to one Se(1), one Se(2), one Se(4), and one Se(5) atom to form corner-sharing AlSe4 tetrahedra. The Al(2)-Se(1) bond length is 2.39 Å. The Al(2)-Se(2) bond length is 2.39 Å. The Al(2)-Se(4) bond length is 2.39 Å. The Al(2)-Se(5) bond length is 2.40 Å. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a water-like geometry to one Tl(2), one Al(1), and one Al(2) atom. In the second Se site, Se(2) is bonded in a water-like geometry to two equivalent Tl(2), one Al(1), and one Al(2) atom. In the third Se site, Se(3) is bonded in a water-like geometry to two equivalent Tl(2) and two equivalent Al(1) atoms. In the fourth Se site, Se(4) is bonded in a water-like geometry to two equivalent Tl(2) and two equivalent Al(2) atoms. In the fifth Se site, Se(5) is bonded in a water-like geometry to one Tl(2), one Al(1), and one Al(2) atom.