NONRADIATIVE ELECTRONIC DEEXCITATION TIME SCALES IN METAL-CLUSTERS

The lifetimes due to Auger-electron emission for a hole on a deep elec tronic shell of neutral and charged sodium clusters are studied for di fferent sizes. We consider spherical clusters and calculate the Auger- transition probabilities using the energy levels and wave functions ca lculated in the local-density approximation. We obtain that Auger emis sion processes are energetically not allowed for neutral and positivel y charged sodium clusters. In general, the Anger probabilities in smal l Na-N(-) clusters are remarkably different from the atomic ones and e xhibit a rich size dependence. The Auger decay times of most of the cl uster sizes studied are orders of magnitude larger than in atoms and m ight be comparable with typical fragmentation times. [S0163-1829(98)07 107-0].