Single rotational product propensity in the photodissociation of HOD

Photodissociation of HOD from the (B) over tilde state has been studied using the high resolution rydberg tagging time-of-flight (TOF) technique. The TOF spectra show an unusually strong population (approximate to 50%) for a single rotational state for the OD(A(2)Sigma, v = 0) fragments. Through theoretical studies, this phenomenon, which we have labeled the single rotational product propensity, is attributed to a dynamically constrained threshold effect in the photodissociation of the HOD molecule on the (B) over tilde state.