  The sensitive dependence of the cluster ion dissociation behavior on the
elastic response of the target metal is experimentally demonstrated. Five types
of metal are bombarded with cluster ions consisting of thousands of argon atoms
at an incident kinetic energy per atom of less than 10 eV. A mass spectroscopic
analysis of dissociated ions such as dimer or trimer is carried out. The
dissociation rate is found to be significantly different for each metal. The
relationship between the dissociation rate and the impulsive stress at the
contact between the cluster ion and the metal is investigated. The impulsive
stress is calculated based on the Youngs modulus of the cluster ion and the
metal, under the assumption that the collision is initially elastic. As a
result, magnitude correlation in the dissociation rate well corresponds with
that in the impulsive stress. This result is important in that it suggests a
new method to evaluate mechanical property of materials such as Youngs modulus
by analyzing the collision with nanocluster ions.
