Absorption parameters in electron diffraction theory

Abstract

Abstract Values of the parameter Vg/Vg are calculated for 100 kv electrons as a function of the reflection vector g for different crystal temperatures and for a number of different materials. It is shown that the usual assumption made, namely setting V0 ′ = Vg ′ = 0·1 Vg independent of g or material, is often a very poor approximation. Calculations based on the inelastic scattering mechanisms involved show that for a given value of g the ratio Vg '/Vg increases with increasing temperature and increasing atomic weight of the material. For a given temperature and material, Vg '/ g increases approximately linearly with g over a wide range of g values.