From supramolecular triangle to heteroleptic rhombus: a simple bridge can make a difference.

Multicomponent, self-assembled rhomboidal constructs are reported, in which bis-terpyridines possessing 120° or 60° directionality and Zn(II) or Cd(II) in a stoichiometric ratio (1 : 1 : 2) initially form rhomboid and triangle mixtures; whereas, a tris-terpyridine reacts with the 60°-based bis-ligand and metal to quantitatively form a heteroleptic, centrally fused, rhomboidal structure.