No abstract

The energy-resolved collision-induced dissociation method is applied to measure the fragmentation patterns, cross sections, and dissociation energies of small anionic silver clusters (Agn−,n=2–11). The main reaction channels are found to be loss of atom and loss of dimer, with dimer loss favored for odd n values. The dissociation energies for the loss of atom, D0(Agn−1−–Ag), show strong even–odd alternation. Threshold models that account for collisional activation efficiency, kinetic shifts, and competitive shifts are employed to obtain dissociation energies. A critical examination of the models is performed using a thermochemical cycle comparing sequential atom loss with dimer loss.