Hannover 2010 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
MO: Fachverband Molekülphysik
MO 33: Cluster II
MO 33.1: Talk
Friday, March 12, 2010, 14:00–14:15, F 102
The observation of electronic energy bands in argon clusters — •Marko Förstel1,2, Melanie Mucke1, Tiberiu Arion1, Toralf Lischke1, Alex Bradshaw1,3, and Uwe Hergenhahn1 — 1Max-Planck-Institut für Plasmaphysik, 85748 Garching — 2Max-Planck-Institut für Kernphysik, 69117 Heidelberg — 3Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin
We have investigated the 3p valence band of argon clusters near the photoionization threshold. Detection of low kinetic energy electrons was achieved by using a newly constructed magnetic bottle type spectrometer. Ar clusters were produced in a supersonic expansion. In our experiments, we have varied the expectation value of the cluster size distribution, ⟨ N⟩, from 50-1000 atoms by changing the expansion conditions. A strong feature at ca. 15 eV binding energy shows a photon energy dependence typical of electronic energy band dispersion. A feature with a similar dispersion occurs in the ordered solid at approximately the same photon energy. This first observation of band dispersion in a rare gas cluster indicates that bulk-like electronic properties are already present in clusters of a few hundred atoms. The cluster size dependence of the dispersion will be discussed in the presentation.