Collective Excitation in Silver Cluster Anions and Kations

Positive and negative silver cluster ions are produced by sputtering of solid silver by 25 keV Xe+ bombaxdment. After mass selection, collinear ion beam depletion is used to measure absolute photofragmentation cross-sections in the photon energy range from ħω = 2.0 to 5.7 eV. Giant resonances are found which can be interpreted in terms of a collective electron oscillation. For spherical clusters (e.g., Ag19−, Ag21+) single resonances dominate the spectra, whereas deformation (e.g., Ag9−, Ag11+) induces a splitting into two components

Collective Excitation in Silver Cluster Anions and Kations

Positive and negative silver cluster ions are produced by sputtering of solid silver by 25 keV Xe+ bombaxdment. After mass selection, collinear ion beam depletion is used to measure absolute photofragmentation cross-sections in the photon energy range from ħω = 2.0 to 5.7 eV. Giant resonances are found which can be interpreted in terms of a collective electron oscillation. For spherical clusters (e.g., Ag19−, Ag21+) single resonances dominate the spectra, whereas deformation (e.g., Ag9−, Ag11+) induces a splitting into two components