Atomic orbital alignment and coherence in N2O photodissociation at 193.3 nm

Strong recoil-frame orbital alignment is observed in the (OD2)-D-1 product following photodissociation of N2O at 193.3 nm. Velocity map imaging allows for investigation of the angular distribution of this alignment, providing insight into the dynamics in the frame of the molecule. Analysis of the re sults using a rigorous quantum mechanical theory yields alignment anisotrop y parameters having direct physical significance. This alignment is dominat ed by strong incoherent parallel and perpendicular contributions. In additi on, evidence is shown of a contribution from a perpendicular coherence. The se results provide detailed insight into the dynamics of the photodissociat ion process and the nature of the electronic transitions responsible for th e initial excitation.