RbH4O3 crystallizes in the orthorhombic Fdd2 space group. Rb(1) is bonded in a 10-coordinate geometry to one H(2), one H(3), two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) and one O(4) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one Rb(1), one O(2), and one O(4) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to one Rb(1), one O(3), and one O(4) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(3) and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to four equivalent Rb(1) and two equivalent H(1) atoms. In the second O site, O(2) is bonded in a water-like geometry to four equivalent Rb(1) and two equivalent H(2) atoms. In the third O site, O(3) is bonded in a water-like geometry to four equivalent Rb(1), one H(3), and one H(4) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one H(1), one H(2), one H(3), and one H(4) atom.
RbH4O3 crystallizes in the orthorhombic Fdd2 space group. Rb(1) is bonded in a 10-coordinate geometry to one H(2), one H(3), two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. The Rb(1)-H(2) bond length is 3.07 Å. The Rb(1)-H(3) bond length is 3.09 Å. There is one shorter (3.13 Å) and one longer (3.14 Å) Rb(1)-O(1) bond length. There is one shorter (3.07 Å) and one longer (3.12 Å) Rb(1)-O(2) bond length. There are a spread of Rb(1)-O(3) bond distances ranging from 3.07-3.17 Å. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) and one O(4) atom. The H(1)-O(1) bond length is 1.01 Å. The H(1)-O(4) bond length is 1.70 Å. In the second H site, H(2) is bonded in a distorted single-bond geometry to one Rb(1), one O(2), and one O(4) atom. The H(2)-O(2) bond length is 1.01 Å. The H(2)-O(4) bond length is 1.67 Å. In the third H site, H(3) is bonded in a distorted single-bond geometry to one Rb(1), one O(3), and one O(4) atom. The H(3)-O(3) bond length is 1.01 Å. The H(3)-O(4) bond length is 1.65 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(3) and one O(4) atom. The H(4)-O(3) bond length is 1.00 Å. The H(4)-O(4) bond length is 1.72 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to four equivalent Rb(1) and two equivalent H(1) atoms. In the second O site, O(2) is bonded in a water-like geometry to four equivalent Rb(1) and two equivalent H(2) atoms. In the third O site, O(3) is bonded in a water-like geometry to four equivalent Rb(1), one H(3), and one H(4) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one H(1), one H(2), one H(3), and one H(4) atom.