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arXiv · 0710.3721

Electronic correlations in graphite and carbon nanotubes from Auger spectroscopy

E. Perfetto·M. Cini·S. Ugenti·P. Castrucci·M. Scarselli·M. De Crescenzi·F. Rosei·M. A. El Khakani
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Abstract

We have determined the screened on-site Coulomb repulsion in graphite and single wall carbon nanotubes by measuring their Auger spectra and performing a new theoretical analysis based on an extended Cini-Sawatzky approach where only one fit parameter is employed. The experimental lineshape is very well reproduced by the theory and this allows to determine the value of the screened on-site repulsion between $2p$ states, which is found to be 2.1 eV in graphite and 4.6 eV in nanotubes. The latter is robust by varying the nanotube radius from 1 to 2 nm.

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E. Perfetto, M. Cini, S. Ugenti, P. Castrucci, M. Scarselli, M. De Crescenzi, F. Rosei, M. A. El Khakani. 2007-10-19. Electronic correlations in graphite and carbon nanotubes from Auger spectroscopy. https://doi.org/10.1103/physrevb.76.233408

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