Huge Quantum Symmetry Effect in the O + O-2 Exchange Reaction

We report extensive, full quantum-mechanical calculations for the O-16 + (OO)-O-16-O-16 -> (OO)-O-16-O-16 + O-16 collisions, for both inelastic and atom exchange processes, using a time-independent method based on hyperspherical coordinates. The rates obtained in the present study are much larger than the previously reported ones for this system. The discrepancy is attributed to a huge symmetry effect that was missing in the studies so far. This effect differs from the well-known isotope effect. Importance of this quantum effect is further confirmed by comparison with results for the O-16 + (OO)-O-18-O-18 -> (OO)-O-16-O-18 + O-18, exchange reaction.