Experimental evidence for resonant electron scattering in C70/MoS2

Using high resolution electron energy loss spectroscopy (HREELS) we have studied the vibrational excitations in C70 overlayer grown epitaxially on MoS2(0001). All vibrational features of C70 were found to fall in the range of its infrared or Raman modes. The inelastic electron scattering cross sections exhibit an anomalous enhancement at the primary electron energy Ep ∼ 3.7 eV, indicating a resonant behavior. This resonance can be attributed to the temmporary trap of some incident electrons in the lowest σ∗-state derived band of solid C70 which results in an increase of the electron-sample interaction time.