Na3Tl4 crystallizes in the trigonal R3m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one Tl(3) and three equivalent Tl(4) atoms to form distorted NaTl4 tetrahedra that share corners with three equivalent Na(2)Tl7 tetrahedra, corners with three equivalent Tl(1)Na4Tl3 tetrahedra, and corners with six equivalent Na(1)Tl4 tetrahedra. In the second Na site, Na(2) is bonded to one Tl(2), three equivalent Tl(1), and three equivalent Tl(3) atoms to form distorted NaTl7 tetrahedra that share corners with three equivalent Na(1)Tl4 tetrahedra, corners with three equivalent Tl(1)Na4Tl3 tetrahedra, edges with three equivalent Tl(1)Na4Tl3 tetrahedra, and edges with six equivalent Na(2)Tl7 tetrahedra. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one Tl(1), three equivalent Tl(2), and three equivalent Tl(3) atoms. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to one Na(3), three equivalent Na(2), and three equivalent Tl(3) atoms to form distorted TlNa4Tl3 tetrahedra that share corners with three equivalent Na(1)Tl4 tetrahedra, corners with three equivalent Na(2)Tl7 tetrahedra, edges with three equivalent Na(2)Tl7 tetrahedra, and edges with six equivalent Tl(1)Na4Tl3 tetrahedra. In the second Tl site, Tl(2) is bonded in a 4-coordinate geometry to one Na(2), three equivalent Na(3), and one Tl(3) atom. In the third Tl site, Tl(3) is bonded in a 11-coordinate geometry to one Na(1), three equivalent Na(2), three equivalent Na(3), one Tl(2), and three equivalent Tl(1) atoms. In the fourth Tl site, Tl(4) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Na(1) atoms.
Na3Tl4 crystallizes in the trigonal R3m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one Tl(3) and three equivalent Tl(4) atoms to form distorted NaTl4 tetrahedra that share corners with three equivalent Na(2)Tl7 tetrahedra, corners with three equivalent Tl(1)Na4Tl3 tetrahedra, and corners with six equivalent Na(1)Tl4 tetrahedra. The Na(1)-Tl(3) bond length is 3.36 Å. All Na(1)-Tl(4) bond lengths are 3.29 Å. In the second Na site, Na(2) is bonded to one Tl(2), three equivalent Tl(1), and three equivalent Tl(3) atoms to form distorted NaTl7 tetrahedra that share corners with three equivalent Na(1)Tl4 tetrahedra, corners with three equivalent Tl(1)Na4Tl3 tetrahedra, edges with three equivalent Tl(1)Na4Tl3 tetrahedra, and edges with six equivalent Na(2)Tl7 tetrahedra. The Na(2)-Tl(2) bond length is 3.39 Å. All Na(2)-Tl(1) bond lengths are 3.22 Å. All Na(2)-Tl(3) bond lengths are 3.77 Å. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one Tl(1), three equivalent Tl(2), and three equivalent Tl(3) atoms. The Na(3)-Tl(1) bond length is 3.21 Å. All Na(3)-Tl(2) bond lengths are 3.34 Å. All Na(3)-Tl(3) bond lengths are 3.66 Å. There are four inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to one Na(3), three equivalent Na(2), and three equivalent Tl(3) atoms to form distorted TlNa4Tl3 tetrahedra that share corners with three equivalent Na(1)Tl4 tetrahedra, corners with three equivalent Na(2)Tl7 tetrahedra, edges with three equivalent Na(2)Tl7 tetrahedra, and edges with six equivalent Tl(1)Na4Tl3 tetrahedra. All Tl(1)-Tl(3) bond lengths are 3.36 Å. In the second Tl site, Tl(2) is bonded in a 4-coordinate geometry to one Na(2), three equivalent Na(3), and one Tl(3) atom. The Tl(2)-Tl(3) bond length is 3.17 Å. In the third Tl site, Tl(3) is bonded in a 11-coordinate geometry to one Na(1), three equivalent Na(2), three equivalent Na(3), one Tl(2), and three equivalent Tl(1) atoms. In the fourth Tl site, Tl(4) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Na(1) atoms.