To understand the contribution of each ligand to the stability of a given cluster, we have applied the protocol specified in Section II D. We have estimated two contributions to the overall interaction energy (∆E T int (L i )) of a given ligand L i . We first evaluate the stabilizing contribution of the interaction of the ligand in a specific coordination shell (∆E Zn Int (L i )) with Zn(II). Second, we evaluate a destabilizing factor (∆E CS f (L i ))) that represents the energy penalty required for the inclusion of a ligand into a coordination shell in the absence of the metal. In other words, ∆E CS f (L i ) represents the energy required to form a specific coordination shell. We show all the results from these calculations in Tables and.