An ab initio study of the primary hydration and proton transfer of CF3SO3H and CF3O(CF2)2SO3H: Effects of the hybrid functional and inclusion of diffuse functions

► Proton dissociation first occurred in each system upon addition of 3 H2O molecules. ► A solvent separated state was found in each system upon addition of 4 H2O molecules. ► Enhanced electron withdrawing of the β CF2 did not affect water binding energies. ► Inclusion of diffuse functions had negligible effects on the structural parameters. ► Nearly identical results were obtained using the X3LYP and B3LYP functional.