Practical Electron Microscopy and Database

Based on Theory on Inelastic Mean Free Path (IMFP) of Electrons, the electron mean free paths are well known in two energy regimes: at high energies, where they are predicted either with Bethe(-like) equations or with the more accurate optical models based on the free-electron-gas approximation, and at very low energies, where they are calculated either with experimental data on electron lifetimes or with first-principles calculations.

Figure 4809a. Electron mean free path of some elements at different kinetic energies.

Figure 4809b. Mean free paths at different kinetic energies up to 2000 eV, for Ag, Al, NA, PMMA, Si, and SiO₂.

Figure 4809c. Mean free paths at the kinetic energy range below 250 eV, for Ag, Al, GaAs, NA, PMMA, and Si.

Figure 4809d. Mean free paths at high kinetic energies for Si and SiO₂.

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 [6 -  11].

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