Berlin 2001 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MO: Molekülphysik
MO 6: Dissociation and other Collision Processes
MO 6.8: Vortrag
Dienstag, 3. April 2001, 17:45–18:00, H1058
Cage effect and HCl photodissociation in rare gas matrices — •Volker Berghof, M. Dickgiesser, and N. Schwentner — Freie Universiät Berlin, Institut für Experimentalphysik
Photodissociation of HCl on the repulsive A1 Π state in matrix serves as a benchmark system for modelling of solid state photoreactions. Contradictory experimental dissociation efficiencies resulted form monitoring the growth of H and Cl fragments. We report on the implementation of an FTIR spectrometer in a set–up using synchrotron radiation for VUV irradiation and in addition UV and visible luminescence spectroscopy. Dissociation efficiencies for monomers and dimers are determined separately and systematic deviations of the fragment growth curves compared to the depletion of HCl according to the IR spectra are demonstrated. The monomer dissociation quantum efficiencies of only 5 % in Krypton for an H atom kinetic energy of 3 eV provides a serious challenge to the calculation which predict significantly higher values. For Xenon matrices contributions form charge transfer states leading to harpoon reactions and the formation of ionic products are discussed.