Fragmentation of doubly charged argon clusters

摘要: Fragmentation of doubly charged argon clusters is reported. Neutral are excited with monochromatized synchrotron radiation in the energy regime argonL 3/L 2 absorption edges (240–260 eV) leading predominantly to cluster dication formation. All particles detected a photoelectron-photoion-photoion-concidence (PEPIPICO) experiment. Symmetric and asymmetric charge separation reactions (Coulomb explosion) identified for below critical size stable The peak shapes coincidence signals investigated as function neutral size. Characteristic changes shape observed which used derive fragmentation mechanisms involving sequential evaporation neutrals before after separation. spectra indicate accordance low kinetic releases occurring large dissociative dications (Ar 2+ , withn>50) that due distances momenta both singly fragments not any more directed into opposite direction, it typical Coulomb explosion. results compared collision induced mass selected well photon stimulated desorption condensed argon.