An Experiment on Ion Beam Collisions with Argon Clusters

Abstract

An experiment on ion beam impact with molecular clusters was performed. Large argon clusters of about 10⁴ atoms/cluster were produced in a high vacuum region with a supersonic expansion technique. Fragment ions were released from the large argon clusters because of the impact of a 3 keV Ar⁺ beam and were analyzed with a mass spectrometer. Small-sized fragment ions were easily detected, however, hardly any larger-sized fragment ions were detected. The collision process between energetic particles and cluster atoms was simulated on the basis of a molecular dynamics model. Experimental fragment ion measurements could be generally explained from an evaporation and fragmentation mechanism for the clusters.

KEYWORDS:

• molecular cluster
• ion beam
• collision
• fragmentation
• molecular dynamics simulation