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Theoretical models and calculations are combined with experimental optical data to determine a model energy-loss function for SiO2. Sum-rule checks and comparisons with experimental information are made to insure overall consistency of the model. The model energy-loss function is employed to calculate electron inelastic mean free paths and stopping powers for electrons with energies ? 10 keV in SiO2.

A theoretical description of the inelastic interactions of electrons with solid polystyrene is presented. The response of the valence electrons to energy and momentum transfers is determined by a model insulator theory; carbon K-shell ionization cross sections are derived from atomic, generalized oscillator strengths. Contributions to the inverse mean free path and stopping power due to these two excitation processes are derived and tabulated for incident electrons with energies from 10 eV to 10 keV. Electron ranges in the continuous-slowing-down approximation are calculated and tabulated for electrons with energies from 15 eV to 10 keV.

The continuous-slowing-down-approximation range and range straggling for electrons with energies ? 10 keV in Al, Au, Ag, and Cu are calculated. The mean energy loss per unit pathlength, or the stopping power, is described by a statistical electron gas model. A correction to the stopping power due to the Z31 effect is included. Comparisons of the calculated CSDA ranges with experimental data are made.

A statistical model is described and employed to calculate inverse mean free paths and stopping powers for electrons of energies from a few eV to 10 keV above the Fermi level in Al, Si, Ni, Cu, Ag, and Au. Brief tables of mean free paths and stopping powers for these solids are presented. In some cases graphical displays of inverse mean free paths and stopping powers are also included. The calculations based on this model are discussed and compared with previous work.

A theoretical description of the inelastic interactions of low-energy electrons (E?10 keV) with solid organic insulators is presented. The response of the valence electrons to energy and momentum transfers is inferred from a model for the energy-loss function with parameters fixed by optical data. With this model energy-loss function, inverse mean free path and stopping power due to interactions with the valence electrons are calculated for several organic solids. Contributions to the inverse mean free path and stopping power due to K-shell ionization in carbon, nitrogen, and oxygen are obtained from theoretical atomic generalized oscillator strengths. Simple, analytical formulae are deduced which allow predictions of mean free paths and stopping powers for electrons in the energy range 100 eV?E?10 keV to be made for a large group of organic solids.

The prospects for obtaining better theoretical calculations of experimentally interesting electron interaction effects, over a wide range of electron energies, are now considerably improved through the development of models for valence electron excitation in simple insulators and through the availability of theoretical atomic generalized oscillator strengths for inner shell electron excitation in several low-Z atomic systems. We describe briefly the way in which this information may be used to calculate mean free paths, stopping powers, and electron slowing-down spectra in Al metal and the insulator Al2O3.