Fragmentation dynamics of argon clusters (Ar[sub n], n=2 to 11) following electron-impact ionization: Modeling and comparison with experiment

International audienceThe fragmentation dynamics of argon clusters ionized by electron impact is investigated for initial cluster sizes up to n=11 atoms. The dynamics of the argon atoms is modeled using a mixed quantum-classical method in which the nuclei are treated classically and the transitions between electronic states quantum mechanically. The potential-energy surfaces are derived from a diatomics-in-molecules model with the addition of the induced dipole-induced dipole and spin-orbit interactions. The results show extensive and fast fragmentation. The dimer is the most abundant ionic fragment, with a proportion increasing from 66% for n=2 to a maximum of 95% for n=6 and then decreasing down to 67% for n=11. The next abundant fragment is the monomer for n