Porous Supramolecular Networks Constructed of One-Dimensional Metal–Organic Chains: Carbon Dioxide and Iodine Capture

In
search of porous materials for selective sorption and iodine inclusion,
we have found two networks made of chains with a kink at the metal
nodes held together by supramolecular interactions (H-bond and π···π
stacking). The solvent can be removed and replaced reversibly without
loss of crystallinity, as demonstrated by single-crystal-to-single-crystal
crystallography. In contrast, iodine uptake degrades the crystallinity
to amorphous, and it regains its crystalline state after removal of
the iodine at 200 °C. Slight differences in behavior of the sorption
and inclusion properties between the tetrahedral metal nodes, Zn and
Co, are associated with the size of the nodes. An important feature
is the extent of iodine that can be included between the chains that
is doubled with temperature from 30 to 100 °C and exceeds the
weight in mass of the compounds.