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arXiv · 0810.4818

Reversible phase transformation and doubly-charged anions at the surface of simple cubic RbC60

Roberto Macovez·Andrea Goldoni·Luca Petaccia·Ingrid Marenne·Paul A. Bruehwiler·Petra Rudolf
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Abstract

The simple cubic phase of a RbC60 thin film has been studied using photoelectron spectroscopy. The simple cubic-to-dimer transition is found to be reversible at the film surface. A sharp Fermi edge is observed and a lower limit of 0.5 eV is found for the surface Hubbard U, pointing to a strongly-correlated metallic character of thin-film simple cubic RbC60. A molecular charge state is identified in the valence band and core level photoemission spectra which arises from C602- anions and contributes to the spectral intensity at the Fermi level.

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Roberto Macovez, Andrea Goldoni, Luca Petaccia, Ingrid Marenne, Paul A. Bruehwiler, Petra Rudolf. 2008-10-27. Reversible phase transformation and doubly-charged anions at the surface of simple cubic RbC60. https://doi.org/10.1103/physrevlett.101.236403

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