Lifetimes and wave functions of ozone metastable vibrational states near the dissociation limit in full symmetry approach

TL;DR

This paper calculates energies, lifetimes, and wave functions of ozone's vibrational states near the dissociation limit using hyperspherical coordinates and symmetry considerations, providing insights into resonance states and vibrational dynamics.

Contribution

It introduces an efficient method combining hyperspherical coordinates and complex absorbing potentials to study ozone vibrational states near dissociation, including symmetry effects and quantum number correspondence.

Findings

Calculated energies and lifetimes of vibrational states above dissociation limit.

Demonstrated symmetry restrictions prevent certain dissociations.

Achieved good agreement with experimental vibrational energies.

Abstract

Energies and lifetimes (widths) of vibrational states above the lowest dissociation limit of $^{16}$O$_3$ were determined using a previously-developed efficient approach, which combines hyperspherical coordinates and a complex absorbing potential. The calculations are based on a recently-computed potential energy surface of ozone determined with a spectroscopic accuracy [J. Chem. Phys. {\bf 139}, 134307 (2013)]. The effect of permutational symmetry on rovibrational dynamics and the density of resonance states in O$_3$ is discussed in detail. Correspondence between quantum numbers appropriate for short- and long-range parts of wave functions of the rovibrational continuum is established. It is shown, by symmetry arguments, that the allowed purely vibrational ($J=0$) levels of $^{16}$O$_3$ and $^{18}$O$_3$, both made of bosons with zero nuclear spin, cannot dissociate on the ground state potential energy surface. Energies and wave functions of bound states of the ozone isotopologue $^{16}$O$_3$ with rotational angular momentum $J=0$ and 1 up to the dissociation threshold were also computed. For bound levels, good agreement with experimental energies is found: The RMS deviation between observed and calculated vibrational energies is 1~\cm. Rotational constants were determined and used for a simple identification of vibrational modes of calculated levels.