Kinematic diffraction is the approach to study diffraction phenomena by neglecting

multiple scattering Scattering is a term used in physics to describe a wide range of physical processes where moving particles or radiation of some form, such as light or sound, are forced to deviate from a straight trajectory by localized non-uniformities (including ...

. For linear

wave equation The (two-way) wave equation is a second-order linear partial differential equation for the description of waves or standing wave fields — as they occur in classical physics — such as mechanical waves (e.g. water waves, sound waves and s ...

s, it thus consists in summing the contribution of the partial waves emanating from the different scatterers, where only the incident field drives the scattering. As a consequence, the far-field amplitude essentially corresponds to the

Fourier transform A Fourier transform (FT) is a mathematical transform that decomposes functions into frequency components, which are represented by the output of the transform as a function of frequency. Most commonly functions of time or space are transformed, ...

of the scattering length density. It is typically understood as the Born approximation applied to a regular arrangement of scatterers, as appropriate for

X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

. The corresponding full (non-perturbative) theory is called the

dynamical theory of diffraction The dynamical theory of diffraction describes the interaction of waves with a regular lattice. The wave fields traditionally described are X-rays, neutrons or electrons and the regular lattice are atomic crystal structures or nanometer-scale multi ...

References

{{CMP-stub Diffraction