Hannover 2010 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

A: Fachverband Atomphysik

A 12: Atomic Clusters I

A 12.6: Vortrag

Mittwoch, 10. März 2010, 15:45–16:00, F 303

Electronic Properties of Transition Metal Doped Silicon Clusters — •Jochen Rittmann¹, Konstantin Hirsch², Christian Kasigkeit², Philipp Klar², Andreas Langenberg¹, Fabian Lofink², Jürgen Probst², Marlene Vogel², Jörg Wittich², Vicente Zamudio-Bayer², Thomas Möller², Bernd von Issendorff³, and Tobias Lau¹ — ¹Helmholtz-Zentrum Berlin für Materialien und Energie, Institut für Methoden und Instrumentierung der Synchrotronstrahlung, Albert-Einstein-Str. 15, 12489 Berlin — ²Technische Universität Berlin, Institut für Optik und Atomare Physik, Hardenbergstr. 36, 10623 Berlin — ³Universität Freiburg, Fakultät für Physik, Stefan-Meier-Str. 21, 79104 Freiburg

Size selected transition metal doped silicon clusters have been studied with resonant 2p x-ray absorption spectroscopy. Despite the different number of valence electrons, nearly identical local electronic structures are found at the dopant atoms in TiSi₁₆⁺, VSi₁₆⁺, and CrSi₁₆⁺. Additional measurements of the direct 2p photoionization as well as spectroscopy on the valence electrons of MSi_n⁺ clusters, (M=V, Ti, Cr; n=15-17) allow us to determine the band gab, which is predicted to be exceptional high for the very symmetric MSi₁₆⁺ clusters (M=V, Ti, Cr). The experimental data can be understood in the spherical potential model. The data indicate strongly interlinked electronic and geometric properties: While the transition metal atoms impose a geometric rearrangement on the silicon cluster, the interaction with the highly symmetric silicon cage determines the electronic structure of the transition metal dopants.