Angular anisotropy of products in the photodissociation of propene at 157 nm

The dynamics of photodissociation of propene has been investigated at 157 nm in a molecular-beam apparatus using photofragment translational spectroscopy and photoionization produced with a synchrotron. We measured angular anisotropy parameters β of several products as a function of kinetic energy. Atomic H has an isotropic angular distribution, H2 has a small negative β, and fragments due to C–C bond rupture have a small positive β. According to these measurements we suggest that the 21A′(π−3p) state has a major contribution on excitation at 157 nm. Photolysis of CD3CHCH2 reveals site effects on the angular distributions of products.