CdSeO3.SeO2 crystallizes in the monoclinic C2/c space group. Cd(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing CdO6 octahedra. Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Se(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Cd(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cd(1) and one Se(1) atom.
CdSeO3.SeO2 crystallizes in the monoclinic C2/c space group. Cd(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form edge-sharing CdO6 octahedra. Both Cd(1)-O(3) bond lengths are 2.28 Å. There are two shorter (2.29 Å) and two longer (2.32 Å) Cd(1)-O(2) bond lengths. Se(1) is bonded in a trigonal non-coplanar geometry to one O(1), one O(2), and one O(3) atom. The Se(1)-O(1) bond length is 1.83 Å. The Se(1)-O(2) bond length is 1.69 Å. The Se(1)-O(3) bond length is 1.67 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Se(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Cd(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cd(1) and one Se(1) atom.