The metal-to-ligand ratio was varied from 0.17:1 to 6:1 while keeping the concentration of AdDB constant at 1.5 mM. The amount of Cu(NO3)2 was systematically changed from 0.25 mM to 9 mM. These experiments resulted in several observations: (i) an excess of ligand results in the formation of flower-like structures, (ii) an equimolar ratio or an excess of metal salt results in the formation of hexagonal prism crystals; the crystals become smaller upon the use of an increasing amount of the metal salt, and (iii) at a ratio of M:L 0.65:1 both prismatic and nascent flower-like crystals begin to appear (Figure ).