RbUC3O8 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded in a 10-coordinate geometry to one O(3), one O(4), one O(5), one O(7), two equivalent O(1), two equivalent O(6), and two equivalent O(8) atoms. U(1) is bonded in a distorted pentagonal bipyramidal geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. There are three inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(5) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(4) and one O(6) atom. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(7) and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Rb(1), one U(1), and one C(2) atom. In the second O site, O(5) is bonded in a distorted single-bond geometry to one Rb(1), one U(1), and one C(1) atom. In the third O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one C(2) atom. In the fourth O site, O(7) is bonded in a distorted single-bond geometry to one Rb(1), one U(1), and one C(3) atom. In the fifth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Rb(1), one U(1), and one C(3) atom. In the sixth O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one U(1) atom. In the seventh O site, O(2) is bonded in a single-bond geometry to one U(1) atom. In the eighth O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), one U(1), and one C(1) atom.
RbUC3O8 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded in a 10-coordinate geometry to one O(3), one O(4), one O(5), one O(7), two equivalent O(1), two equivalent O(6), and two equivalent O(8) atoms. The Rb(1)-O(3) bond length is 3.41 Å. The Rb(1)-O(4) bond length is 3.05 Å. The Rb(1)-O(5) bond length is 3.30 Å. The Rb(1)-O(7) bond length is 3.18 Å. There is one shorter (2.98 Å) and one longer (3.50 Å) Rb(1)-O(1) bond length. There is one shorter (3.01 Å) and one longer (3.13 Å) Rb(1)-O(6) bond length. There is one shorter (3.13 Å) and one longer (3.31 Å) Rb(1)-O(8) bond length. U(1) is bonded in a distorted pentagonal bipyramidal geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. The U(1)-O(1) bond length is 1.81 Å. The U(1)-O(2) bond length is 1.80 Å. The U(1)-O(3) bond length is 2.44 Å. The U(1)-O(4) bond length is 2.37 Å. The U(1)-O(5) bond length is 2.36 Å. The U(1)-O(7) bond length is 2.46 Å. The U(1)-O(8) bond length is 2.51 Å. There are three inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(5) atom. The C(1)-O(3) bond length is 1.27 Å. The C(1)-O(5) bond length is 1.27 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(4) and one O(6) atom. The C(2)-O(4) bond length is 1.30 Å. The C(2)-O(6) bond length is 1.24 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(7) and one O(8) atom. The C(3)-O(7) bond length is 1.27 Å. The C(3)-O(8) bond length is 1.27 Å. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Rb(1), one U(1), and one C(2) atom. In the second O site, O(5) is bonded in a distorted single-bond geometry to one Rb(1), one U(1), and one C(1) atom. In the third O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one C(2) atom. In the fourth O site, O(7) is bonded in a distorted single-bond geometry to one Rb(1), one U(1), and one C(3) atom. In the fifth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Rb(1), one U(1), and one C(3) atom. In the sixth O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one U(1) atom. In the seventh O site, O(2) is bonded in a single-bond geometry to one U(1) atom. In the eighth O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), one U(1), and one C(1) atom.