Rb2Co(SO7)2 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded to one O(1), one O(3), one O(4), one O(5), two equivalent O(2), and two equivalent O(7) atoms to form distorted RbO8 hexagonal bipyramids that share corners with two equivalent Rb(1)O8 hexagonal bipyramids, corners with two equivalent Co(1)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra,  an edgeedge with one Rb(1)O8 hexagonal bipyramid, and edges with two equivalent S(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-40°. Co(1) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms to form distorted CoO6 octahedra that share corners with four equivalent Rb(1)O8 hexagonal bipyramids. S(1) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form SO4 tetrahedra that share corners with two equivalent Rb(1)O8 hexagonal bipyramids and edges with two equivalent Rb(1)O8 hexagonal bipyramids. There are seven inequivalent O sites. In the first O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one S(1) atom. In the second O site, O(1) is bonded in a distorted single-bond geometry to one Rb(1) and one S(1) atom. In the third O site, O(2) is bonded in a single-bond geometry to two equivalent Rb(1) and one S(1) atom. In the fourth O site, O(3) is bonded in a single-bond geometry to one Rb(1) and one Co(1) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1) and one S(1) atom. In the sixth O site, O(5) is bonded in a distorted single-bond geometry to one Rb(1) and one Co(1) atom. In the seventh O site, O(6) is bonded in a single-bond geometry to one Co(1) atom.
Rb2Co(SO7)2 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded to one O(1), one O(3), one O(4), one O(5), two equivalent O(2), and two equivalent O(7) atoms to form distorted RbO8 hexagonal bipyramids that share corners with two equivalent Rb(1)O8 hexagonal bipyramids, corners with two equivalent Co(1)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra,  an edgeedge with one Rb(1)O8 hexagonal bipyramid, and edges with two equivalent S(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 31-40°. The Rb(1)-O(1) bond length is 3.01 Å. The Rb(1)-O(3) bond length is 3.33 Å. The Rb(1)-O(4) bond length is 2.98 Å. The Rb(1)-O(5) bond length is 3.11 Å. There is one shorter (3.25 Å) and one longer (3.32 Å) Rb(1)-O(2) bond length. There is one shorter (2.93 Å) and one longer (3.03 Å) Rb(1)-O(7) bond length. Co(1) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms to form distorted CoO6 octahedra that share corners with four equivalent Rb(1)O8 hexagonal bipyramids. Both Co(1)-O(3) bond lengths are 1.77 Å. Both Co(1)-O(5) bond lengths are 1.77 Å. Both Co(1)-O(6) bond lengths are 1.79 Å. S(1) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form SO4 tetrahedra that share corners with two equivalent Rb(1)O8 hexagonal bipyramids and edges with two equivalent Rb(1)O8 hexagonal bipyramids. The S(1)-O(1) bond length is 1.48 Å. The S(1)-O(2) bond length is 1.48 Å. The S(1)-O(4) bond length is 1.50 Å. The S(1)-O(7) bond length is 1.49 Å. There are seven inequivalent O sites. In the first O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one S(1) atom. In the second O site, O(1) is bonded in a distorted single-bond geometry to one Rb(1) and one S(1) atom. In the third O site, O(2) is bonded in a single-bond geometry to two equivalent Rb(1) and one S(1) atom. In the fourth O site, O(3) is bonded in a single-bond geometry to one Rb(1) and one Co(1) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1) and one S(1) atom. In the sixth O site, O(5) is bonded in a distorted single-bond geometry to one Rb(1) and one Co(1) atom. In the seventh O site, O(6) is bonded in a single-bond geometry to one Co(1) atom.