Rb3TlF6 is (Cubic) Perovskite-like structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to twelve equivalent F(1) atoms to form RbF12 cuboctahedra that share corners with twelve equivalent Rb(1)F12 cuboctahedra, faces with six equivalent Rb(1)F12 cuboctahedra, faces with four equivalent Rb(2)F6 octahedra, and faces with four equivalent Tl(1)F6 octahedra. In the second Rb site, Rb(2) is bonded to six equivalent F(1) atoms to form RbF6 octahedra that share corners with six equivalent Tl(1)F6 octahedra and faces with eight equivalent Rb(1)F12 cuboctahedra. The corner-sharing octahedra are not tilted. Tl(1) is bonded to six equivalent F(1) atoms to form TlF6 octahedra that share corners with six equivalent Rb(2)F6 octahedra and faces with eight equivalent Rb(1)F12 cuboctahedra. The corner-sharing octahedra are not tilted. F(1) is bonded in a distorted linear geometry to one Rb(2), four equivalent Rb(1), and one Tl(1) atom.
Rb3TlF6 is (Cubic) Perovskite-like structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to twelve equivalent F(1) atoms to form RbF12 cuboctahedra that share corners with twelve equivalent Rb(1)F12 cuboctahedra, faces with six equivalent Rb(1)F12 cuboctahedra, faces with four equivalent Rb(2)F6 octahedra, and faces with four equivalent Tl(1)F6 octahedra. All Rb(1)-F(1) bond lengths are 3.37 Å. In the second Rb site, Rb(2) is bonded to six equivalent F(1) atoms to form RbF6 octahedra that share corners with six equivalent Tl(1)F6 octahedra and faces with eight equivalent Rb(1)F12 cuboctahedra. The corner-sharing octahedra are not tilted. All Rb(2)-F(1) bond lengths are 2.59 Å. Tl(1) is bonded to six equivalent F(1) atoms to form TlF6 octahedra that share corners with six equivalent Rb(2)F6 octahedra and faces with eight equivalent Rb(1)F12 cuboctahedra. The corner-sharing octahedra are not tilted. All Tl(1)-F(1) bond lengths are 2.16 Å. F(1) is bonded in a distorted linear geometry to one Rb(2), four equivalent Rb(1), and one Tl(1) atom.