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A: Atomphysik

A 19: Fullerene (gemeinsam mit dem FV Molekülphysik)

A 19.10: Vortrag

Donnerstag, 6. April 2000, 16:15–16:30, HS VIII

Vibrational Spectroscopy of Gas Phase Metal Carbide Clusters and Nanocrystals — •Gert von Helden¹, Deniz van Heijnsbergen¹, Michael A. Duncan², and Gerard Meijer¹ — ¹FOM Institute for Plasmaphysics Rijnhuizen, Edisonbaan 14, NL-3430 BE Nieuwegein, The Netherlands — ²Department of Chemistry, University of Georgia, Athens, Georgia 30602, U.S.A

Neutral Ti₈C₁₂ and Ti₁₄C₁₃ clusters are produced in the gas phase with pulsed-nozzle laser vaporization. Infrared multiphoton excitation with a pulsed free electron laser results in thermionic electron emission for these clusters, and the parent molecular ions are detected. Multiphoton ionization is strongly enhanced on vibrational resonances of

these clusters, making it possible to observe infrared resonance enhanced multiphoton ionization (IR-REMPI) spectra. These spectra indicate C–C bonding for the “met-cars” while Ti₁₄C₁₃ has remarkable similarities to bulk TiC.

[1] D. van Heijnsbergen, G. von Helden, M. A. Duncan, André J.A. van Roij, G. Meijer, Phys. Rev. Lett. 83, ?? (1999).