Influence of Parent Bending Motion on Branching at a Conical Intersection in thePhotodissociation of CX3I (X = H, D, F)

摘要

The influence of coupling between Born-Oppenheimer potential energy surfaces ispervasive in the dissociation of polyatomic molecules from excited electronic states, often resulting in branching between energetically allowed fragmentation pathways. Many experiments examine the effect of curve crossings or conical intersections along the dissociation pathway by mapping the product internal state distributions or the branching as a function of excitation energy. In the case we consider below, the radial derivative coupling between two repulsive states is only nonzero at non-C3v nuclear geometries on the excited state surfaces. By exciting molecules with nonzero quanta in e-symmetry bending vibration to the repulsive surfaces, we prepare a dissociative wave function with increased probability amplitude away from C3v geometries. The experiment tests if this results in the dissociating molecules sampling regions of the conical intersection where coupling is greater and brings about a change in the branching ratio between the two energetically allowed product channels.