Rb6Co2O7 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), and three equivalent O(4) atoms. In the third Rb site, Rb(3) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Co(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing CoO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Co(1) atoms. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one Co(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one Co(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(3), three equivalent Rb(2), and one Co(1) atom.
Rb6Co2O7 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. The Rb(1)-O(1) bond length is 2.92 Å. The Rb(1)-O(4) bond length is 2.90 Å. There is one shorter (2.88 Å) and one longer (2.98 Å) Rb(1)-O(2) bond length. There is one shorter (2.84 Å) and one longer (3.09 Å) Rb(1)-O(3) bond length. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), and three equivalent O(4) atoms. The Rb(2)-O(1) bond length is 3.00 Å. The Rb(2)-O(2) bond length is 3.03 Å. The Rb(2)-O(3) bond length is 2.87 Å. There are a spread of Rb(2)-O(4) bond distances ranging from 2.98-3.38 Å. In the third Rb site, Rb(3) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There is one shorter (2.79 Å) and one longer (2.81 Å) Rb(3)-O(2) bond length. There is one shorter (2.75 Å) and one longer (2.80 Å) Rb(3)-O(3) bond length. There is one shorter (3.06 Å) and one longer (3.36 Å) Rb(3)-O(4) bond length. Co(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing CoO4 tetrahedra. The Co(1)-O(1) bond length is 1.86 Å. The Co(1)-O(2) bond length is 1.78 Å. The Co(1)-O(3) bond length is 1.79 Å. The Co(1)-O(4) bond length is 1.79 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Co(1) atoms. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one Co(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one Co(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(3), three equivalent Rb(2), and one Co(1) atom.