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By exploiting the self-organization of metal salt-loaded diblock copolymer micelles followed by a plasma-induced removal of the polymer matrix, well-separated gold particles ranging in size from 1.6 to 10 nm have been prepared on top of diamond substrates. X-ray-induced photoelectron spectra of the valence-band region demonstrate that the electronic properties of such nanoparticles essentially reflect the metallic behavior of the bulk material as can be inferred from the evolution of the d-band shape and the finite density of states at the Fermi energy. This experimentally extends the lower limit for the metallic state of supported Au particles down to a diameter of 1.6 nm

The electronic structure of liquid transition metals has been studied by time resolved photoelectron spectroscopy. Distinct changes in the valence band structure across the solid-liquid phase transitions have been observed for Pd, Mo and W. In the case of Pd the changes on melting are caused by a change in the photoemission process itself. For Nb, Mo, Ta and W we suggest a change in the atomic short range order from the bcc structure to an fcc-like short range order in the liquid state which causes a marked change in the valence band spectra of Mo and W due to the filling up of the pronounced gap in the density of states near the Fermi level. The measurements show that time resolved photoelectron spectroscopy can be used to study high temperature oxidation processes on the microsecond time scale.

The electronic structure of liquid tungsten has been studied by time-resolved photoelectron spectroscopy on laser pulse molten surface layers. The valence band spectra reveal distinct changes of the electronic structure across the solid-liquid phase transition which are interpreted by marked changes of the short-range order on melting which change qualitatively the valence electron density of states.

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