RbU2SbS8 crystallizes in the monoclinic Cm space group. Rb(1) is bonded in a 8-coordinate geometry to one S(4), one S(5), two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms. U(1) is bonded in a 8-coordinate geometry to one S(4), one S(5), two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms. Sb(1) is bonded in a distorted see-saw-like geometry to one S(4), one S(5), and two equivalent S(3) atoms. There are five inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent U(1), and one S(2) atom. In the second S site, S(2) is bonded in a distorted square co-planar geometry to one Rb(1), two equivalent U(1), and one S(1) atom. In the third S site, S(3) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent U(1), and one Sb(1) atom. In the fourth S site, S(4) is bonded to one Rb(1), two equivalent U(1), and one Sb(1) atom to form distorted corner-sharing SRbU2Sb trigonal pyramids. In the fifth S site, S(5) is bonded to one Rb(1), two equivalent U(1), and one Sb(1) atom to form distorted corner-sharing SRbU2Sb trigonal pyramids.
RbU2SbS8 crystallizes in the monoclinic Cm space group. Rb(1) is bonded in a 8-coordinate geometry to one S(4), one S(5), two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms. The Rb(1)-S(4) bond length is 3.42 Å. The Rb(1)-S(5) bond length is 3.41 Å. Both Rb(1)-S(1) bond lengths are 3.46 Å. Both Rb(1)-S(2) bond lengths are 3.48 Å. Both Rb(1)-S(3) bond lengths are 3.30 Å. U(1) is bonded in a 8-coordinate geometry to one S(4), one S(5), two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms. The U(1)-S(4) bond length is 2.87 Å. The U(1)-S(5) bond length is 2.87 Å. There is one shorter (2.80 Å) and one longer (2.83 Å) U(1)-S(1) bond length. There is one shorter (2.79 Å) and one longer (2.82 Å) U(1)-S(2) bond length. Both U(1)-S(3) bond lengths are 2.72 Å. Sb(1) is bonded in a distorted see-saw-like geometry to one S(4), one S(5), and two equivalent S(3) atoms. The Sb(1)-S(4) bond length is 2.45 Å. The Sb(1)-S(5) bond length is 2.44 Å. Both Sb(1)-S(3) bond lengths are 2.70 Å. There are five inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent U(1), and one S(2) atom. The S(1)-S(2) bond length is 2.07 Å. In the second S site, S(2) is bonded in a distorted square co-planar geometry to one Rb(1), two equivalent U(1), and one S(1) atom. In the third S site, S(3) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent U(1), and one Sb(1) atom. In the fourth S site, S(4) is bonded to one Rb(1), two equivalent U(1), and one Sb(1) atom to form distorted corner-sharing SRbU2Sb trigonal pyramids. In the fifth S site, S(5) is bonded to one Rb(1), two equivalent U(1), and one Sb(1) atom to form distorted corner-sharing SRbU2Sb trigonal pyramids.