Tb5Tl3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to six equivalent Tl(1) atoms. In the second Tb site, Tb(2) is bonded in a 5-coordinate geometry to five equivalent Tl(1) atoms. Tl(1) is bonded in a 9-coordinate geometry to four equivalent Tb(1) and five equivalent Tb(2) atoms.
Tb5Tl3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to six equivalent Tl(1) atoms. All Tb(1)-Tl(1) bond lengths are 3.21 Å. In the second Tb site, Tb(2) is bonded in a 5-coordinate geometry to five equivalent Tl(1) atoms. There are a spread of Tb(2)-Tl(1) bond distances ranging from 3.15-3.66 Å. Tl(1) is bonded in a 9-coordinate geometry to four equivalent Tb(1) and five equivalent Tb(2) atoms.