An analytical expression for the calculation of electron mean free paths in solids

A simple analytical expression for the calculation of the inelastic-scattering mean free path for electrons in free-electron-like metals has been derived on the basis of a dielectric formalism. Good agreement with experimental data for energies greater than 200 eV has been demonstrated. By extending the concept of a one-mode excitation spectrum, an analogous formula applicable to semiconductors, insulators and non-free-electron-like metals has been derived which also compares well with experimental data. (orig.)