Tl3SnI5 crystallizes in the orthorhombic P2_12_12_1 space group. There are three inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 3-coordinate geometry to one I(1), one I(4), and one I(5) atom. In the second Tl site, Tl(2) is bonded in a 2-coordinate geometry to one I(1) and one I(2) atom. In the third Tl site, Tl(3) is bonded in a 4-coordinate geometry to one I(1), one I(5), and two equivalent I(2) atoms. Sn(1) is bonded in a square pyramidal geometry to one I(1), one I(2), one I(3), one I(4), and one I(5) atom. There are five inequivalent I sites. In the first I site, I(5) is bonded in a 3-coordinate geometry to one Tl(1), one Tl(3), and one Sn(1) atom. In the second I site, I(1) is bonded in a rectangular see-saw-like geometry to one Tl(1), one Tl(2), one Tl(3), and one Sn(1) atom. In the third I site, I(2) is bonded in a 4-coordinate geometry to one Tl(2), two equivalent Tl(3), and one Sn(1) atom. In the fourth I site, I(3) is bonded in a single-bond geometry to one Sn(1) atom. In the fifth I site, I(4) is bonded in a 1-coordinate geometry to one Tl(1) and one Sn(1) atom.
Tl3SnI5 crystallizes in the orthorhombic P2_12_12_1 space group. There are three inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 3-coordinate geometry to one I(1), one I(4), and one I(5) atom. The Tl(1)-I(1) bond length is 3.56 Å. The Tl(1)-I(4) bond length is 3.53 Å. The Tl(1)-I(5) bond length is 3.49 Å. In the second Tl site, Tl(2) is bonded in a 2-coordinate geometry to one I(1) and one I(2) atom. The Tl(2)-I(1) bond length is 3.47 Å. The Tl(2)-I(2) bond length is 3.49 Å. In the third Tl site, Tl(3) is bonded in a 4-coordinate geometry to one I(1), one I(5), and two equivalent I(2) atoms. The Tl(3)-I(1) bond length is 3.55 Å. The Tl(3)-I(5) bond length is 3.57 Å. There is one shorter (3.54 Å) and one longer (3.58 Å) Tl(3)-I(2) bond length. Sn(1) is bonded in a square pyramidal geometry to one I(1), one I(2), one I(3), one I(4), and one I(5) atom. The Sn(1)-I(1) bond length is 3.29 Å. The Sn(1)-I(2) bond length is 3.33 Å. The Sn(1)-I(3) bond length is 3.10 Å. The Sn(1)-I(4) bond length is 3.07 Å. The Sn(1)-I(5) bond length is 3.32 Å. There are five inequivalent I sites. In the first I site, I(5) is bonded in a 3-coordinate geometry to one Tl(1), one Tl(3), and one Sn(1) atom. In the second I site, I(1) is bonded in a rectangular see-saw-like geometry to one Tl(1), one Tl(2), one Tl(3), and one Sn(1) atom. In the third I site, I(2) is bonded in a 4-coordinate geometry to one Tl(2), two equivalent Tl(3), and one Sn(1) atom. In the fourth I site, I(3) is bonded in a single-bond geometry to one Sn(1) atom. In the fifth I site, I(4) is bonded in a 1-coordinate geometry to one Tl(1) and one Sn(1) atom.