The dynamics of Br(2Pj) formation in the photodissociation of vinyl and perfluorovinyl bromides (original) (raw)

The photodissociation dynamics of vinyl bromide and perfluorovinyl bromide have been investigated at 234 nm using a photofragment ion imaging technique coupled with a state-selective [2+1] resonance-enhanced multiphoton ionization scheme. The nascent Br atoms stem from the primary C–Br bond dissociation leading to the formation of C2H3(X̃) and Br(2Pj;j=1/2,3/2). The obtained translational energy distributions have been well fitted by a single Boltzmann and three Gaussian functions. Boltzmann component has not been observed in the perfluorovinyl bromide. The repulsive A′3(n,σ*) state has been considered as the origin of the highest Gaussian components. Middle translational energy components with Gaussian shapes are produced from the A″1(π,σ*) and/or A″3(π,σ*) which are very close in energy. Low-energy Gaussian components are produced via predissociation from the A′1(π,π*) state. The assignments have also been supported by the recoil anisotropy corresponding to the individual componen...