Cd2H2SO6 crystallizes in the monoclinic C2/c space group. Cd(1) is bonded to one O(2), two equivalent O(1), and three equivalent O(3) atoms to form distorted CdO6 octahedra that share corners with two equivalent Cd(1)O6 octahedra, corners with three equivalent S(1)O4 tetrahedra, and edges with three equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles are 54°. H(1) is bonded in a single-bond geometry to one O(3) atom. S(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form SO4 tetrahedra that share corners with six equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Cd(1) and one S(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cd(1) and one S(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to three equivalent Cd(1) and one H(1) atom.
Cd2H2SO6 crystallizes in the monoclinic C2/c space group. Cd(1) is bonded to one O(2), two equivalent O(1), and three equivalent O(3) atoms to form distorted CdO6 octahedra that share corners with two equivalent Cd(1)O6 octahedra, corners with three equivalent S(1)O4 tetrahedra, and edges with three equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles are 54°. The Cd(1)-O(2) bond length is 2.37 Å. There is one shorter (2.39 Å) and one longer (2.40 Å) Cd(1)-O(1) bond length. There are a spread of Cd(1)-O(3) bond distances ranging from 2.20-2.29 Å. H(1) is bonded in a single-bond geometry to one O(3) atom. The H(1)-O(3) bond length is 0.97 Å. S(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form SO4 tetrahedra that share corners with six equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. Both S(1)-O(1) bond lengths are 1.48 Å. Both S(1)-O(2) bond lengths are 1.47 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Cd(1) and one S(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Cd(1) and one S(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to three equivalent Cd(1) and one H(1) atom.