Metal Ligand Aromatic Cation−π Interactions

Cation−π interactions are important noncovalent bonding forces. This review covers a special type of cation−π interactions, the metal ligand aromatic cation−π (MLACπ) interaction, where ligands that are coordinated to a metal ion interact with aromatic groups. These interactions have been observed in metalloproteins, metal complexes, biomimetic metal complexes, and when DNA and RNA interact with metal cations. The energy of MLACπ interactions in different systems has been calculated by quantum chemical methods and was found to vary from 1 to 30 kcal/mol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)