Rotational quantum state dependent alternations in the angular momentum polarization of O 2(a 1Δ g) formed in the UV photodissociation of O 3

Abstract

REMPI-TOF studies of the UV photodissociation of O 3 at 270 nm have allowed the translational anisotropy and angular momentum polarization of the O 2(a 1Δ g) molecular photofragment to be determined. Alignment and orientation moments have been measured for O 2(a 1Δ g, v = 0) using a selection of rotational transitions probing values of J = 15–27 in the (1,0) and (2,0) bands of the highly perturbed (2 + 1) d 1Π g ←← a 1Δ g REMPI spectrum. The fragments exhibit the anisotropic vector correlations expected from a prompt dissociation via the 1B 2 ← 1A 1 transition. However, we observe that the moments describing angular momentum polarization of odd J states are consistently lower in magnitude than those of even J states, resulting in a clear alternation in the moments observed across a rotational branch.