N-H and N-C Bond Dissociation Pathways in Ultraviolet Photodissociation of Dimethylamine.

We investigated the interlinked N-H and N-C photochemistry of primary and secondary amines via the state-resolved detection of vibrationally excited CH product and H atom product by 200-235 nm dimethylamine photodissociation using resonance-enhanced multiphoton ionization (REMPI) and velocity map imaging (VMI) techniques. The out-of-plane bending (ν) vibrationally excited CH showed a bimodal translational energy distribution that became unimodal with a near-zero product yield at longer photolysis wavelengths (λ). In contrast, a unimodal distribution was observed for the C-H stretching (ν) vibrationally excited CH products with an almost constant product yield in the examined λ region.