Interpenetrating 3D Framework Based on Inorganic Lanthanide Sulfate Rod Secondary Building Unit Involving In Situ Cleavage of a Sulfide–Sulfide Bond

One novel two-fold interpenetrating 3D coordination polymer [Dy(L)(SO4)(H2O)] (1) (H2L = 6-hydroxypyridine-3-carboxylic acid) has been synthesized and characterized by elemental analyses and single-crystal X-ray diffraction, respectively. Interestingly, L and sulfate anions came from the in situ cleavage of a sulfide–sulfide bond of the flexible 6,6′-dithiodinicotinic acid in the hydrothermal reactions. In the structure of 1, the L ligands connect the (–Dy–SO4–)∞ inorganic rod secondary building units to form a 3D (3,5)-connected (42.65.83)(42.6) net, interlocking the 3D network leads to a twofold parallel interpenetration network. In addition, thermal stability of 1 was also investigated.