Dissociative xenon ion capture by neutral argon clusters

• Published in: International journal of mass spectrometry and ion processes 1993-11, Vol.129, p.67-78
• Main Authors: Lezius, M., Scheier, P., Foltin, M., Kolibiar, M., Cleveland, C.L., Landman, U., Märk, T.D.
• Format: Article
• Language: English
• Subjects: Argon clusters; Atomic and molecular clusters; Atomic and molecular collision processes and interactions; Atomic and molecular physics; Chemical reactions, energy disposal, and angular distribution, as studied by atomic and molecular beams; Dissociative ion capture; Exact sciences and technology; Ion/molecule reactions; Magic numbers; Molecular dynamics; Physics; Scattering of atoms, molecules and ions; Studies of special atoms, molecules and their ions; clusters
• ISSN: 0168-1176; 1873-2801
• DOI: 10.1016/0168-1176(93)87030-V

In this paper we describe and discuss a new approach to the production of van der Waals cluster ions. Instead of ionizing pre-existing neutral clusters by electron impact, Xe + ions interact with neutral Ar m clusters and produce, via a dissociative ion capture process, mixed Ar n Xe + ions. This new ionization mode appears to be softer than electron impact (i.e. it leads to less fragmentation). Measured cluster ion distributions and metastable fragmentation spectra show the anomalous abundance typical of icosahedral shell and subshell closures, which do not appear when argon clusters are ionized by electron impact. Furthermore we have used classical molecular dynamics to simulate ionization via this dissociative ion capture process and found that the agreement between the simulation and the experiment is very good.