Surface Diffraction
Kinematic or elastic backscattering occurs when low energy (1-100 eV) electrons impinge on a clean, well-ordered crystalline specimen. It is assumed that each electron undergoes only one scattering event, and incident electron beam is described as a plane wave with the wavelength:
Scientists use inverse space to describe the periodicity of the lattice and the interaction of the plane wave with the sample surface. In inverse (or "k-space") space, the wave vector of the incident and scattered waves are and, respectively,
and constructive interference occurs at the Laue condition:
where (h,k,l) is a set of integers and
is a vector of the reciprocal lattice.
Read more about this topic: Low-energy Electron Microscopy
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