Crystal structure of the coordination polymer [Co(bipy)1.5(NO3)2]·CS2 (bipy=4,4′-bipyridine), a new motif for a network sustained by ‘T-shape’ building blocks

The crystal structure of the coordination polymer [Co(bipy)1.5(NO3)2]·1 (bipy=4,4′-bipyridine), reveals that, if crystallized in the presence of CS2, it exists as a novel two-dimensional bilayer motif. This is in contrast to what might have been expected since a one-dimensional molecular-ladder motif is exhibited by 1 when crystallized in the presence of MeCN or CHCl3. A molecule of CS2 is clathrated inside the bilayer via what appear to be C–H···S hydrogen bonds from 4,4′-bipyridine ligands. Adjacent bilayers pack efficiently in a gear-like fashion. The existence of this new structural supramolecular isomer is rationalized on the basis of a template effect from the CS2 guest molecule.