Eur. Phys. J. D (2012) 66: 254
https://doi.org/10.1140/epjd/e2012-30178-1

Regular Article

Collective excitations in the electron energy loss spectra of C₆₀

¹ CNR-Istituto di Metodologie Inorganiche e dei Plasmi, Area della Ricerca di Roma 1, CP 10, 00015 Monterotondo Scalo, Italy
² Dipartimento di Fisica and Unità CNISM, Università di Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy
³ Frankfurt Institute for Advanced Studies, Goethe-Universität, Ruth-Moufang-Str. 1, 60438 Frankfurt am Main, Germany
⁴ St. Petersburg State Polytechnic University, Polytekhnicheskaya ul. 29, 195251 St. Petersburg, Russia

^a e-mail: verkhovtsev@fias.uni-frankfurt.de
^b On leave from A.F. Ioffe Physical Technical Institute, St. Petersburg, Russia.

Received: 15 March 2012
Received in final form: 9 July 2012
Published online: 4 October 2012

Abstract

The results of a joint experimental and theoretical investigation of the collective excitations in the energy loss spectra of the C₆₀ fullerene are presented. A variation of the shape of the electron energy loss spectrum has been observed experimentally as the scattering angle increases. This variation is described within the frame of a new theoretical model which treats the fullerene as a spherical shell of a finite width and accounts for the two modes of the surface plasmon and for the volume plasmon as well. It is shown that at small angles the inelastic scattering cross section is determined mostly by the excitation of the symmetric mode of the surface plasmon, while at larger angles the excitation of the antisymmetric surface and volume plasmons becomes prominent.