Photofragment spectroscopy and dynamics of the visible photodissociation of ozone

Abstract

We report collision-free coherent anti-Stokes Raman scattering (CARS) spectra of the O2 fragment formed in the photodissociation of ozone at 532 and 578 nm. From these spectra we have extracted the nascent electronic, vibrational, rotational, and translational energy distributions of the photofragments. The O2 fragment is produced only in the ground 3Σ−g electronic state, even though the 1Δg excited state is energetically allowed. High (J≊23 to 51) rotational states in the first five vibrational levels of O2(3Σ−g) are populated in the photodissociation. For both photolysis wavelengths most of the available energy, 65%–67%, appears in translation, while 15%–18% is in rotation, and 17%–18% is in vibration. These energy distributions are discussed in terms of simple models of the dissociation dynamics.