A comparison of inelastic electron scattering models based on delta -function representations of the Bethe surface

Abstract

A comparison is made of the inverse mean free path and stopping power of low- and medium-energy electrons in solids as computed by means of some different simple models of the generalized oscillator strength. The considered generalized oscillator strength models consist of an optical oscillator strength, which is either derived from experimental optical data or modelled from atomic data or from the local plasma approximation, complemented with a suitable algorithm to extend it to the nonzero momentum transfer region. The extension algorithms adopted here are delta -function representations of the Bethe surface similar to the so-called 'one-mode' models of the free-electron gas.