Photoionization of vibrationally hot CH3 and CF3 -: art. no. 234303

Vibrationally hot CH3 and CF3 were produced by the 266 nm photodissociation of CH3I and CF3I, respectively, and probed by single-photon ionization at 118 nm. Comparison of the ion images of the CH3 and CF3 fragments with those of the complementary I atoms, and with previous measurements of the product branching fractions, allowed the determination of the relative photoion yields as a function of the vibrational energy of the molecular radical. Some general ideas about the internal-energy dependence of photoionization cross sections are also discussed. (C) 2005 American Institute of Physics.