SIZE DEPENDENCE OF GASEOUS CLUSTER REACTIVITY AND EVAPORATION DYNAMICS AS A MECHANISTIC PROBE

Two different types of cluster studies were carried out in our laboratory. In one, gaseous niobium metal clusters are synthesized by laser ablation and supersonic expansion in helium and detected by using excimer one-photon ionization-mass spectrometry methods. The dependence of their chemical reactivity (toward some carbon compounds) on size is examined and used as a new mechanistic probe. In the other types of cluster studies, the mechanisms of the evaporation of one and two CsI molecules from individual mass-selected [Cs(CsI)n]+ clusters (made by sputtering techniques) are determined from a study of the kinetic energy released and its distribution during the evaporation process.