Absorption parameters in electron diffraction theory

Abstract

Values of the parameter V_g/V_g 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 ′ = V_g ′ = 0·1 V_g 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 V_g '/V_g increases with increasing temperature and increasing atomic weight of the material. For a given temperature and material, V_g '/ _g increases approximately linearly with g over a wide range of g values.