Lifetimes and decay mechanisms of isotopically substituted ozone above the dissociation threshold: matching quantum and classical dynamics.

Energies and lifetimes of vibrational resonances were computed for 18 O-enriched isotopologue 50 O 3 = { 16 O 16 O 18 O and 16 O 18 O 16 O} of the ozone molecule using hyperspherical coordinates and the method of complex absorbing potential. Various types of scattering resonances were identified, including roaming OO-O rotational states, the series corresponding to continuation of bound vibrational resonances of highly excited bending or symmetric stretching vibrational modes. Such a series become metastable above the dissociation limit. The coupling between the vibrationally excited O 2 fragment and rotational roaming gives rise to Feshbach type resonances in ozone. Different paths for the formation and decay of symmetric 16 O 18 O 16 O and asymmetric species 16 O 16 O 18 O were also identified. The symmetry properties of the total rovibronic wave functions of the 18 O-enriched isotopologues are discussed in the context of allowed dissociation channels.