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Temperature broadening of the microscopically obtained optical absorption of open-shell clusters is studied with Nalo as an example. The method used is the time-dependent local-density approximation, combined with the coupling to the shape fluctuations of the cluster, both in the ground state and in the excited state. In sharp contrast to earlier studies by Pacheco and Broglia, the quantum nature of the fluctuations is fully taken into account. The obtained linewidth is in good agreement with recent experimental data of Knight and collaborators. The breakdown of the so-called plasmon-pole approximation is investigated in detail, and it is found that the reason for this is the fragmentation of the oscillator strength stored in the plasmon line, which is a genuine particle-hole effect both in closed-shell jellium clusters (Na20) and in open-shell metal clusters (Nalo).

The electronic properties of small metal particles within the recently proposed self-consistent spheroidal jellium model [1] are further explored and compared to recent experimental data. Physical properties investigated include ionization potentials, electron affinities and the binding energy of neutral monomers to cationic clusters. The formalism is applied within the size-range 2___N_<41, but could easily be extended beyond N = 41. Finally, we discuss briefly the implications for the study of the dynamical response of open-shell clusters. In sharp contrast to earlier studies the functional is now corrected for self-interaction error, in a way first proposed by Pcdew and Zunger [2]. This enables us to calculate reliable values for the electron affinities within a jellium-based model. This has the advantage, that we can calculate the affinities for Cu for all particle numbers for which experimental data are available. In all cases investigated we obtain excellent agreement with experiment, with pronounced shell-effects both for the electron affinities and for the binding energies, confirming in this way that the abundances map the relative stability of (Me)N clusters, with Me being a sp-metal atom (Na, K, Li, Cu, Ag, Au etc.).

The nonradiative lifetime of excited states near a small {&2 nrn) metal particle is investigated within a purely electromagnetic model. The excited state is described as a point dipole, and the metal particle is characterized by its self-consistently obtained nonlocal density-density correlation function. Resonant coupling, between excited states of adsorbates and various electronic excitations of the metal particle, is shown to be an important lifetime-determining decay channel.