Crystal Structure of Tetraammine Zinc(II) Peroxodisulfate and Barium Peroxodisulfate Tetrahydrate

Zinc(II) tetraammine peroxodisulfate [Zn(NH₃)₄]S₂O₈ (I) and barium peroxodisulfate tetrahydrate BaS₂O₈·4H₂O (II) were synthesized by interaction of an aqueous solution of ammonium peroxodisulfate with a zinc peroxide and barium hydroxide, respectively. The crystal structures (CIF file CCDC nos. 2311248 (I) and 2311249 (II)) were determined by single crystal X-ray diffraction. The crystal structure of I, for which X-ray powder diffraction structural data were previously reported, has been redetermined and clarified. The crystal packing of I consists of hydrogen-bonded chains parallel to the b-axis connected in a three-dimensional structure with H-bonds between adjacent chains. The compound II is coordination polymer with coordination number of barium cation equal to 9. The crystal packing of II consists of channels in which water molecules are held by H-bonds. Compounds I and II were characterized by DTA and TGA revealing thermal stability up to 170 and 90°C.