Imidazolate anions exhibit stronger interactions with the metal cation than nitrate or the solvent molecules and have a greater influence on the coordination number. Noticeably, it is found that, once Im -anions coordinate with the Zn 2+ , the incorporation of ethanol, water, or nitrate to the complex is only favored up to a total coordination number of 3. In other words, under implicit solvation, ZnIm n X m complexes are stable up to n + m = 3 (for n =1-3). For instance, the complexes ZnImX 2 and ZnIm 2 X are appreciably more stable than their ZnImX 3 , ZnIm 2 X 2 four-fold coordinated counterparts. Note that the nitrate anion exothermically displaces ethanol or water in these complexes (see Figure and Table ). These energetic trends also hold systematically for all the clusters with more than one metal cation explored in this work. Under implicit solvation, the Zn 2+ sites in Zn z Im n X m clusters of any size create a four-fold tetrahedral coordination with Im -anions, but they bind explicit methanol and water molecules or nitrate anions only up to a three-fold coordination. This general behavior guides the initial stages of Zn-Im aggregation, as described in more detail in Sec. 3.2 below. In contrast, in vacuo, these trends only hold for nitrate, and not for ethanol or water, for which the four-fold coordinated complexes (n + m = 4) are predicted to be the most stable. We believe that this might be due to the fact that nitrate ions are negatively charged, and thus the Coulombic repulsions between ligands preclude the full coordination.