Table 4623 lists plasmon energies, full-width-at-half-maximum of plasmon energies, plasmon mean free path, and inelastic mean free path of some common elements and compounds, as well as their crystal structure.
Measurements of numbers of inelastic and elastic mean free paths :
i) t/λi, from EELS spectra, should be recorded with the objective aperture withdrawn. λi is the inelastic mean.
ii) t/λe can be obtained simply by recording the low-loss
spectrum of the specimen with a small objective aperture. λe is the elastic mean
 K. Wong and R. F. Egerton, Correction for the effects of elastic scattering in core-loss quantification, Journal of Microscopy, 178(3), (1995) pp. 198-207.