Photodissociation spectroscopy of Ag4+(N2)m, m=0-4

We have determined photodissociation spectra of Ag-4(+)(N-2)(m=0-4) in the photon energy range from 2.1 to 3.75 eV. The cluster complexes were generated by laser vaporization and their absolute photodissociation cross sections were measured in depletion using a modified reflectron time-of-flight mass spectrometer. The band spectra show significant nonmonotonic variations with increasing N-2 coverage. The experimental data are contrasted with quantum chemical calculations of ground and electronically excited states using density functional as well as post-Hartree-Fock methods. Experiment and theory are in qualitative agreement allowing tentative assignment of the depletion spectra and insight into the relevant bonding interactions. (C) 2000 American Institute of Physics. [S0021-9606(00)01137-5].