Collisions of the gaseous hydroxyl radical and ozone with surfaces of 
sodium chloride or iodide solutions
as well as with the surface of neat water were investigated by  molecular dynamics
simulations. The principal aim was to answer atmospherically relevant questions 
concerning trapping and
accommodation of the OH and O3 species 
at the surface and their uptake into the bulk solution.
Although trapping is substantial for both species, OH adsorbs and absorbs significantly
better than O3. While most of the trapped ozone molecules desorb from the surface
within 50 ps, a significant fraction of hydroxyl radicals remains at the interface
for time intervals exceeding 100 ps. The aqueous surface has also an orientational
effect on the OH species, favoring geometries with the hydrogen pointing to the 
aqueous bulk. The effect of the dissolved salt on the trapping efficiency
is minor, therefore, most likely, atomic ions solvated in aqueous aerosols do 
not act as scavengers of reactive gases in the atmosphere. There are, however, 
frequent and relatively long contacts between the adsorbed  molecules and halide
anions allowing for heterogenous atmospheric chemistry in the interfacial layer.