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PubMed · 16189598

Solid C58 films.

Artur Böttcher·Patrick Weis·Stefan-S Jester·Daniel Löffler·Angela Bihlmeier·Wim Klopper·Manfred M Kappes
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Abstract

A new solid material has been created in ultra high vacuum by utilizing the aggregation process of C58 molecules deposited onto highly oriented pyrolytic graphite from a mass selected low-energy ion beam comprising C58+. Cluster fluxes of up to 3x10(11) ions s-1 cm-2 with impinging kinetic energies of 6+/-0.5 eV were typically applied. Growth of the solid C58 phase proceeds according to the cluster-aggregation-based Volmer-Weber scenario where initially ramified 2D islands transform into 3D pyramid-like structures at higher coverages. The C58 films created exhibit much higher thermal stability than the C60 solid phase. Sublimation of C58 sets in at a temperature of 700 K. Ultraviolet photoionization spectra (He I, 21.2 eV) yield a molecular ionization potential in the range between 6.6 and 7 eV. Density functional and Hartree-Fock theories suggest that the formation of C58 dimers and higher multimers upon deposition/aggregation gives rise to the high thermal stability and unique electronic properties of this material.

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Biomedical EngineeringDimerizationElectronicsFullerenesGraphiteKineticsMicroscopy, Atomic ForceSpectrophotometryTemperatureComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Artur Böttcher, Patrick Weis, Stefan-S Jester, Daniel Löffler, Angela Bihlmeier, Wim Klopper, Manfred M Kappes. 2005-06-16. Solid C58 films.. https://doi.org/10.1039/b505703e

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