Electronic structure of liquid transition metals studied by time resolved photoelectron spectroscopy

The electronic structure of liquid transition metals has been studied by ti me resolved photoelectron spectroscopy. Distinct changes in the valence ban d structure across the solid-liquid phase transitions have been observed fo r Pd, Mo and W. In the case of Pd the changes on melting are caused by a ch ange 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-li ke short range order in the liquid state which causes a marked change in th e valence band spectra of Mo and W due to the ailing up of the pronounced g ap in the density of states near the Fermi level. The measurements show tha t time resolved photoelectron spectroscopy can be used to study high temper ature oxidation processes on the microsecond time scale.