||Understanding fundamental aspects of coordination chemistry is important in the study of catalysis, many enzymatic systems, and even biomedical processes. In the present investigation, gas-phase ion-molecule reactions between an array of heteroaromatic ligands and a series of monopositive metal ions are examined. Production formation,with respect to dimerization or trimerization, is correlated with the electronic configuration of the metal ion and the polydentate properties of the ligand. The orders of relative metal ion binding affinities of the heteroaromatic ligands are determined from ligand exchange techniques in order to establish the influence of the size and electronic configuration of the metal ion and size and flexibility of the aromatic ligand. Typically terpyridine demonstrates the greatest metal ion binding strength, followed by phenanthroline, 2,2'-bipyridine, then pyridine. For many of the monomer metal complexes, a molecule of water may be incorporated at longer reaction times, but this hydration process is not observed for the dimer or trimer complexes.