LASER IONIZATION SPECTROSCOPY OF AG(NH3)(N) CLUSTERS

The ionization and the fragmentation properties of Ag(NH3)(n) heterocl usters have been studied. The measured ion yield spectra near the thre shold for complexes with n = 2-20 indicate strong differences of the c luster geometry in the electronic ground and in the ionized state, res pectively. For smaller clusters (n less than or equal to 6) in the neu tral ground state the nonsolvated Ag atom is localized near the surfac e of the complex. A modification of the surface structure at the trans ition to larger clusters (n greater than or equal to 7) is suggested b y significant changes in the ionization and fragmentation behaviour. P reliminary results of ab initio calculations confirm the conclusion th at due to the correlation interaction between the valence electron and the 4d electrons of the AE atom no solvation effects occur.