3. Precession electron diffraction

The kinematic nature of the interaction between X-rays and matter has made this diffraction technique essential for determining crystalline structures, whether from single crystals or powders. Relevant methods have been developed to achieve this. Electron diffraction, on the other hand, has always been considered unsuitable for this purpose. The fault lies in the dynamic character of the interaction between electrons and matter, not because of the formalism, which is well established, but because of the multiple character of diffraction, linked to the existence of diffraction domains associated with the nodes of the reciprocal grating and leading to the softening of Bragg conditions. As a result, the intensities of the transmitted and diffracted beams are highly dependent on the thickness and orientation of the selected zone, parameters which are rarely known with...