C₆₈: A non-IPR fullerene capable of binding extraordinary amounts of Cs atoms

Abstract

The non-IPR fulleride compound Cs_xC₆₈ was investigated in analogy to previous experiments on Cs_xC₅₈. While the vibrational properties as well as the electronic structure in the valence band range appear to be pretty similar to Cs_xC₅₈, a striking difference could be observed by XPS and Photoemission Microscopy analysis: apparently, C₆₈ forms different phases within a thick film including islands in which it is able to store more than 70 Cs atoms per fullerene cage and to keep these amounts even after annealing over 1100 K. This means that Cs_xC₆₈ constitutes the highest alkali metal doping degree of any Fullerene species known so far. Spatially resolved photoemission analysis also revealed that the Cs-rich fulleride phases constitute a unique chemical state that has never been observed before.

Keywords:

• Alkali metal doping
• ESCA Microscopy
• Fullerene
• isolated pentagon rule
• Raman
• SPEM
• Temperature programmed Desorption
• UPS
• XPS

Additional information

Funding

This work was funded by the DFG Center of Functional Nanostructures (CFN, subproject C4.6). The access to the ESCA Microscopy Beamline at Elettra Synchrotron Laboratory was granted under proposal 20130315. Deutsche Forschungsgemeinschaft.