Deviation from Bragg scattering

In this video we now elaborate on the sample shape effect on the reciprocal lattice nodes in the case of 2-beam electron diffraction, by applying the theory of Fourier transforms. We then use this to describe scattering when we deviate slightly from the perfect Bragg condition, including introducing a new quantity (the "excitation error"), while keeping to a kinematical – i.e. single-scattering – approximation.