Fragmentation of small silicon clusters

Abstract

Recently we have performed accurate ab initio molecular orbital calculations to study the structures and energies of small silicon clusters (Si n , n=2–10). In this work, the ground state binding energies of the clusters have been used to interpret the results of recent photofragmentation experiments on the ionic silicon clusters up to Si 20 +. Fragmentation predominantly yields daughter ions which are energetically most stable, consistent with a unimolecular dissociation mechanism involving vibrationally excited clusters on the ground electronic potential surface. Clusters containing 6, 7 and 10 atoms have been identified as “magic fragments” for these photodissociation processes, consistent with the experimental results.