Host-Guest Interactions in ExBox4+

The host-guest interaction between poly aromatic hydrocarbon/azine and the newly synthesized ExBox(4+) complex is studied with the help of density functional theory. The solvent-phase interaction energy is found to decrease with gradual substitution of methine groups (=CH-) from the six-membered ring of guest molecules with N atoms in the resultant azi-ne@ExBox(4+) complex. The nature of the binding interaction is studied with the help of newly developed noncovalent interaction (NCI) plot program package along with energy decomposition analysis and charge decomposition analysis. The interactions are mostly pi-type van der Waals interactions.