Tl9SbTe6 crystallizes in the tetragonal I4 space group. There are three inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 2-coordinate geometry to three equivalent Te(2) atoms. In the second Tl site, Tl(2) is bonded in a 2-coordinate geometry to one Te(3) and two equivalent Te(2) atoms. In the third Tl site, Tl(3) is bonded to one Te(3) and four equivalent Te(2) atoms to form distorted TlTe5 square pyramids that share corners with four equivalent Sb(1)Te5 square pyramids. Sb(1) is bonded to one Te(1) and four equivalent Te(2) atoms to form distorted SbTe5 square pyramids that share corners with four equivalent Tl(3)Te5 square pyramids. There are three inequivalent Te sites. In the first Te site, Te(1) is bonded in a distorted single-bond geometry to one Sb(1) atom. In the second Te site, Te(2) is bonded in a 7-coordinate geometry to one Tl(3), two equivalent Tl(2), three equivalent Tl(1), and one Sb(1) atom. In the third Te site, Te(3) is bonded in a 5-coordinate geometry to one Tl(3) and four equivalent Tl(2) atoms.
Tl9SbTe6 crystallizes in the tetragonal I4 space group. There are three inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 2-coordinate geometry to three equivalent Te(2) atoms. There are a spread of Tl(1)-Te(2) bond distances ranging from 3.20-3.58 Å. In the second Tl site, Tl(2) is bonded in a 2-coordinate geometry to one Te(3) and two equivalent Te(2) atoms. The Tl(2)-Te(3) bond length is 3.52 Å. There is one shorter (3.19 Å) and one longer (3.36 Å) Tl(2)-Te(2) bond length. In the third Tl site, Tl(3) is bonded to one Te(3) and four equivalent Te(2) atoms to form distorted TlTe5 square pyramids that share corners with four equivalent Sb(1)Te5 square pyramids. The Tl(3)-Te(3) bond length is 3.33 Å. All Tl(3)-Te(2) bond lengths are 3.52 Å. Sb(1) is bonded to one Te(1) and four equivalent Te(2) atoms to form distorted SbTe5 square pyramids that share corners with four equivalent Tl(3)Te5 square pyramids. The Sb(1)-Te(1) bond length is 2.89 Å. All Sb(1)-Te(2) bond lengths are 3.16 Å. There are three inequivalent Te sites. In the first Te site, Te(1) is bonded in a distorted single-bond geometry to one Sb(1) atom. In the second Te site, Te(2) is bonded in a 7-coordinate geometry to one Tl(3), two equivalent Tl(2), three equivalent Tl(1), and one Sb(1) atom. In the third Te site, Te(3) is bonded in a 5-coordinate geometry to one Tl(3) and four equivalent Tl(2) atoms.