Intralayer hydrogen bonding in CdSeO3.H2O

Single crystals of cadmium trioxoselenate(IV) monohydrate were obtained from aqueous solutions of H2SeO3 and [Cd(CH3COO)(2)]. 2H(2)O. CdSeO3 . H2O crystallizes in the MnSeO3 . D2O oP32 type. The structure contains buckled trans [CdSeO3 . H2O](i)(2) layers consisting of strongly distorted, vertex-sharing CdO5(H2O) octahedra and SeO32- ions, both of symmetry m. The H-atom position was also determined, indicating that the H2O molecules have pseudo mm2 symmetry. They form an intralayer hydrogen-bonding scheme with approximately Linear hydrogen bonds of distance d(OH ... O) = 2.903 (3) Angstrom. As a consequence, the [MSeO3 . H2O](i)(2) layers of the [MnSeO3 . D2O] oP32-type monohydrates are held together by van der Waals interactions but not by hydrogen bonds.