Guest–Host Interaction of Coinage Metals in π-Rich Cavities

Abstract

The complexation of coinage metal cations with [2.2.2]paracyclophane and deltaphane has been investigated by means of density functional theory (DFT) calculations employing the PBE0-D3 hybrid functional, which incorporates explicit dispersion corrections to account for the weak intermolecular forces that are important in the systems studied. Natural bond orbital (NBO) analyses, Bader's Atoms in Molecules theory analyses as well as localised molecular orbital – energy decomposition analyses (LMO-EDAs) have been carried out to further investigate the electronic structure and bonding of the complexes. It was found that both cyclophanes bind strongest with gold ions, followed closely by copper ions and lastly silver ions. The two fragments interact in a non-covalent fashion in these complexes and the metal preferentially resides at the periphery of the molecular cavity of the cyclophane.