Reversible phase transformation and doubly charged anions at the surface of simple cubic RbC60.
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 C60(2-) anions and contributes to the spectral intensity at the Fermi level.
Macovez
Roberto
R
Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands. roberto.macovez@icfo.es
Goldoni
Andrea
A
Petaccia
Luca
L
Marenne
Ingrid
I
Brühwiler
Paul A
PA
Rudolf
Petra
P