DFT calculations were applied to an iron/catechol derivative system to investigate their effect on the structure of CPPs as a function of (a) metal valence—Fe+2 and Fe+3 in high- and low-spin states; (b) type of chelating groups in the catechol derivatives and their geometries; and (c) the aliphatic chain length between two chelating groups in a model polydentate ligand. The results indicate that catechol-pyridine and bis-catechol ligands, with Fe+3 salts, are promising combinations to synthesize CPPs. In addition, the inclusion of an aliphatic chain with four carbons between the chelating groups could enhance polymerization versus monomer formation.