Interplay of the volume and surface plasmons in the electron energy loss spectra of C$_{60}$

TL;DR

This study combines experimental and theoretical approaches to analyze how volume and surface plasmons influence the electron energy loss spectra of C60, revealing angle-dependent spectral variations due to plasmon modes.

Contribution

A new theoretical model treating C60 as a finite-width spherical shell that explains angle-dependent plasmon contributions in electron scattering spectra.

Findings

At small angles, symmetric surface plasmon dominates.

At larger angles, antisymmetric surface and volume plasmons become significant.

The model accurately reproduces experimental spectral variations.

Abstract

The results of a joint experimental and theoretical investigation of the C60 collective excitations in the process of inelastic scattering of electrons are presented. The shape of the electron energy loss spectrum is observed to vary when the scattering angle increases. This variation arising due to the electron diffraction of the fullerene shell is described by 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 symmetric mode of the surface plasmon, while at larger angles, the contributions of the antisymmetric surface plasmon and the volume plasmon become prominent.