Validity of the Debye Scattering Equation in Elastic Electron Diffraction

Abstract

THE methods of Debye¹ are accepted in the scattering of electrons by gases, but despite the application to thin films by Germer and White² their use in kinematic electron diffraction from polycrystalline solids has seemed suspect and none of the recent texts on electron diffraction mention the methods. Possibly this is because of a preoccupation with dynamical theory. Many real specimens, however, diffract kinematically and the Debye “gas” equation, if valid for closely packed small crystals, would enable the detailed intensity profile for polycrystalline films to be computed. The objection to the Debye theory is that it neglects interference between atoms situated in different crystals; while this is permissible for a gas of large molecules, it requires justification if the molecules (or small crystals) are densely packed.