Photoelectrons-photoions coincidence spectroscopy for van der Waal clusters using synchrotron light

Photoionization and the fragmentation processes of van der Waal clusters were studied in order to obtain information on their electronic states and configurations. Time of flight spectra were obtained using the Threshold Electron Photon Ion Coincidence (TEPICO) method. Experiments on Fe(CO)5 are discussed. It is shown that most of the energy deposited in the molecule after photoionization is converted into vibrational energy of the CO. An enrichment of the Ne-22 isotope, in the cluster, of about thirty percent was found, resulting from a photon induced fragmentation. The experimentally obtained magic number could be rationalized by a Diatonics In Molecules (DIM) calculation.