Tb3Tl5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 9-coordinate geometry to one Tl(1), four equivalent Tl(2), and four equivalent Tl(3) atoms. In the second Tb site, Tb(2) is bonded in a 10-coordinate geometry to two equivalent Tl(1), four equivalent Tl(2), and four equivalent Tl(3) atoms. There are three inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 11-coordinate geometry to one Tb(1), four equivalent Tb(2), two equivalent Tl(2), and four equivalent Tl(3) atoms. In the second Tl site, Tl(2) is bonded in a 10-coordinate geometry to two equivalent Tb(1), four equivalent Tb(2), one Tl(1), one Tl(2), and two equivalent Tl(3) atoms. In the third Tl site, Tl(3) is bonded in a 10-coordinate geometry to two equivalent Tb(1), four equivalent Tb(2), two equivalent Tl(1), and two equivalent Tl(2) atoms.
Tb3Tl5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 9-coordinate geometry to one Tl(1), four equivalent Tl(2), and four equivalent Tl(3) atoms. The Tb(1)-Tl(1) bond length is 3.08 Å. There are two shorter (3.20 Å) and two longer (3.33 Å) Tb(1)-Tl(2) bond lengths. There are two shorter (3.12 Å) and two longer (3.57 Å) Tb(1)-Tl(3) bond lengths. In the second Tb site, Tb(2) is bonded in a 10-coordinate geometry to two equivalent Tl(1), four equivalent Tl(2), and four equivalent Tl(3) atoms. Both Tb(2)-Tl(1) bond lengths are 3.40 Å. There are two shorter (3.26 Å) and two longer (3.48 Å) Tb(2)-Tl(2) bond lengths. There are two shorter (3.24 Å) and two longer (3.50 Å) Tb(2)-Tl(3) bond lengths. There are three inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 11-coordinate geometry to one Tb(1), four equivalent Tb(2), two equivalent Tl(2), and four equivalent Tl(3) atoms. Both Tl(1)-Tl(2) bond lengths are 3.26 Å. All Tl(1)-Tl(3) bond lengths are 3.30 Å. In the second Tl site, Tl(2) is bonded in a 10-coordinate geometry to two equivalent Tb(1), four equivalent Tb(2), one Tl(1), one Tl(2), and two equivalent Tl(3) atoms. The Tl(2)-Tl(2) bond length is 3.36 Å. Both Tl(2)-Tl(3) bond lengths are 3.21 Å. In the third Tl site, Tl(3) is bonded in a 10-coordinate geometry to two equivalent Tb(1), four equivalent Tb(2), two equivalent Tl(1), and two equivalent Tl(2) atoms.