Min Chevalier Kwon, Jan Pieter Abrahams
High-energy electrons passing through a sample in a transmission electron microscope carry structural information through their interactions with the sample's atoms. Elastically scattered electrons, which undergo no significant energy loss, convey spatial details in their scattering angles and phase shifts. Inelastic scattering transfers energy to the sample, causing ionisation-induced, random structural changes, and thereby reducing the spatial coherence of a crystalline sample. Next to changing the sample's structure, inelastic scattering also reduces the coherence lengths of the electron wave function, further degrading its spatial information. This review examines the mechanisms and impact of combined elastic and inelastic scattering, and discusses their implications for the structural characterisation of biological, organic, and inorganic materials.