Virtual scattering of high-energy electrons by plasmons and valence electrons in silicon

The contribution from plasmon and valence-electron scattering to the higher-order Fourier coefficients of the electron virtual scattering potential (EVSP) is shown to be non-negligible in contradiction to previous assumptions. In particular, calculations are made for this contribution to the EVSP C-0.g(r)(plasmon) for g = 111 in silicon. In contrast to the elastic potential, C-0.g(r)(plasmon) is found to be highly energy dependent, varying by three orders of magnitude between 20 eV and 100 keV. Whilst it is found that the contribution from plasmon scattering is larger than that from tightly bound core states, the relative contribution to the total potential is smaller than that presently resolvable by electron experimental methods at 100 keV.