Thermal diffuse scattering: elastic and coherent

Thermal diffuse scattering (TDS) caused by the interaction of high-energy electrons with phonons has been investigated. An oscillating atom retains all of its elastic scattering capacity, although the vibration changes the spatial distribution of the scattering potential. Therefore, the scattering by the vibrating lattice or phonons is still elastic. Furthermore, the TDS electrons re-main coherent and form the diffuse interference patterns even under the time-averaging assump-tion. Elastic and coherent TDS electrons contribute most of the contrast of Kikuchi lines.