Ho5Tl3 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 5-coordinate geometry to two equivalent Tl(2) and three equivalent Tl(1) atoms. In the second Ho site, Ho(2) is bonded to two equivalent Tl(2) and four equivalent Tl(1) atoms to form distorted corner-sharing HoTl6 octahedra. The corner-sharing octahedral tilt angles range from 0-49°. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 9-coordinate geometry to two equivalent Ho(2), six equivalent Ho(1), and one Tl(1) atom. In the second Tl site, Tl(2) is bonded in a 10-coordinate geometry to two equivalent Ho(2) and eight equivalent Ho(1) atoms.
Ho5Tl3 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 5-coordinate geometry to two equivalent Tl(2) and three equivalent Tl(1) atoms. Both Ho(1)-Tl(2) bond lengths are 3.32 Å. There is one shorter (3.17 Å) and two longer (3.22 Å) Ho(1)-Tl(1) bond lengths. In the second Ho site, Ho(2) is bonded to two equivalent Tl(2) and four equivalent Tl(1) atoms to form distorted corner-sharing HoTl6 octahedra. The corner-sharing octahedral tilt angles range from 0-49°. Both Ho(2)-Tl(2) bond lengths are 3.59 Å. All Ho(2)-Tl(1) bond lengths are 3.12 Å. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 9-coordinate geometry to two equivalent Ho(2), six equivalent Ho(1), and one Tl(1) atom. The Tl(1)-Tl(1) bond length is 3.06 Å. In the second Tl site, Tl(2) is bonded in a 10-coordinate geometry to two equivalent Ho(2) and eight equivalent Ho(1) atoms.