Ozone Photodissociation in the Singlet Channel at 226 nm.

We report the rotational state distribution and vector correlations of the O 2 (a 1 Δ g , v = 0) fragments arising from the 226 nm photodissociation of jet-cooled O 3 . Consistent with previously reported trends, the rotational distribution is shifted to higher rotational states with decreasing wavelength. We observe highly suppressed odd rotational state populations due to a strong Λ-doublet propensity. The measured rotational distribution is in agreement with classical trajectory calculations for the v = 0 products, although the distribution is slightly narrower than predicted. The spatial anisotropy follows the previously observed trend of decreasing β with increasing photon energy with β = 0.72 ± 0.14 for v = 0, j = 38. As expected for a triatomic molecule, the v - j correlation is consistent with v perpendicular to j , but the measured correlation is nonlimiting due, in part, to rotational and translational depolarization. The j -dependent line width of the O 2 (a 1 Δ g ) REMPI spectrum is also discussed in connection with the lifetime of the resonant O 2 (d 1 Π g ) state due to predissociation via the II 1 Π g valence state.