Characteristics and nature of the halogen-bonding interactions between CCl 3 F and ozone: a supermolecular and SAPT study.

The strength and nature of the halogen-bond interactions in CCl3F···O3complexes were examined by means ofab initioquantum-chemical calculations and symmetry-adapted perturbation theory (SAPT). Our calculations predict a trifurcated C–Cl···O interaction for the global minimum of CCl3F···O3complex and several local minima, differing slightly in energy, separated by very low barriers. The calculations, which include a rigorous decomposition of the interaction energies, also indicate that the interaction of CCl3F molecule with O3is characterised by contributions from both electrostatic and dispersion energies, with the contribution of the latter being dominant. The evaluated SAPT interaction energies for the CCl3F···O3complexes are generally in good agreement with those obtained using the supermolecule CCSD(T) method, suggesting that SAPT is a proper method to study the intermolecular interactions in these complexes. [ABSTRACT FROM AUTHOR]