The ultraviolet photodissociation of 2-chlorobutane: an imaging study comparing state-resolved and universal probe techniques

We present an imaging study of the Cl elimination channel in the 193 nm photodissociation of 2-chlorobutane. We compare the results obtained using resonant 2+1 photoionization of the Cl(2P3/2) and Cl*(2P1/2) products with those obtained using single photon ionization of the 2-butyl radical cofragment, and find reasonable agreement between the two techniques. The product translational energy distribution is sharply peaked at ∼50% of the available energy, while the branching fraction to the spin–orbit excited Cl∗ is 0.50. We also present results for H elimination in the 157 nm photodissociation of 2-chlorobutane. The results are interpreted using a simple impulsive model of the dissociation dynamics.