AN ABINITIO INVESTIGATION OF THE SIGNIFICANCE OF THE HOOF INTERMEDIATE IN COUPLING REACTIONS INVOLVING FOOX AND HOX SPECIES

Ab initio calculations are used to investigate the stability and role of HOOF in the reaction of FO with HO radicals. The heat of formation for HOOF is estimated as 0.4+/-2 kcal mol-1 using an isodesmic reaction scheme. Spectroscopic properties of the HOOF intermediate is also provided in order to facilitate its identification. Decomposition pathways of the intermediate are examined. The lowest energy pathway is the formation of F atoms and HO2 radicals and requires 27.2 kcal mol-1 to proceed. Reactions leading to the formation of the HOOF intermediate are examined in regard to their importance in understanding stratospheric chemistry involving the coupling of fluorine and fluorine oxide with HO(x) species in catalytic cycles.