Probing the Fragmentation Pathways of an Argon Dimer in Slow Ion–Dimer Collisions

Abstract

We report the development of a supersonic jet assembly to study electron transfer collisions with atoms, molecules, and van der Waals clusters. A comparative study of Ar monomer and dimer cations is presented for different capture-associated channels with a 2.5 keV/u O2+ projectile beam. For the Ar+ + Ar+ fragmentation channel, the interatomic relaxation channels are discussed. The vacancies of the dimer single site or double site show the dependence on capture mechanisms. In the Ar2+ + Ar+ fragmentation channel, double capture, in addition to the single ionization process, dominates. The orientation effect reflects the maximum yield at around 50 and 130 degrees, and angular distributions are nearly symmetric about the axis perpendicular to the dimer axis.

Keywords

• electron capture
• interatomic relaxation processes
• dimer fragmentation
• orientation effect