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

Energies and lifetimes of vibrational resonances were computed for ¹⁸O-enriched isotopologue ⁵⁰O₃ = {¹⁶O¹⁶O¹⁸O and ¹⁶O¹⁸O¹⁶O} 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 O₂ fragment and rotational roaming gives rise to Feshbach type resonances in ozone. Different paths for the formation and decay of symmetric ¹⁶O¹⁸O¹⁶O and asymmetric species ¹⁶O¹⁶O¹⁸O were also identified. The symmetry properties of the total rovibronic wave functions of the ¹⁸O-enriched isotopologues are discussed in the context of allowed dissociation channels.