Ab initio thermodynamic study of the reaction of CF 2Cl 2 and CHF 2Cl CFCs species with OH radical

Abstract

We report ab initio calculations up to the CCSD(T)/aug-cc-pVQZ and MP4(SDTQ)/aug-cc-pV5Z levels for the OH radical reaction with CF 2Cl 2 and CHF 2Cl CFCs species, aiming to assess the level of calculation required to reproduce experimental thermodynamic data: (I) CF 2Cl 2 + OH → CF 2Cl + HOCl; (II) CHF 2Cl + OH → CF 2Cl + H 2O; (III) CF 2Cl 2 + OH → CFCl 2 + HOF. We found that reaction enthalpies and Gibbs free energies can be evaluated at the CCSD(T)/aug-cc-pVQZ//MP2/aug-cc-pVDZ level, with deviations from experiment of 3%, 5%, 6%, respectively. These results can also be relevant to other studies involving CFCs interactions in large systems.