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

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 نشر من قبل Roberto Macovez
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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