Allyl-A model system for the chemical dynamics of radicals

The allyl radical, C3H5, is probably the currently best understood hydrocarbon radical. It is thus a model system for radical spectroscopy and dynamics. In this Feature Article we summarize the work performed on allyl in our laboratories by various laser spectroscopic techniques and develop a comprehensive picture of the processes occurring in allyl upon photo excitation. This includes the structure of the excited electronic states of the neutral, as well as the ionic, ground state, the coupling phenomena between them, the primary photophysical processes directly after excitation, which occur on a picosecond time scale, and finally the unimolecular dissociation dynamics.