Each point (reflection) in this diffraction pattern is formed by the interference of X-ray scattering through a crystal. The data obtained can be used to determine the crystal structure.
X-ray spectroscopy is a generic name that covers all those spectroscopic techniques used to determine the electronic structure of materials by X-ray excitation. X-ray spectroscopy has a wide range of applications, especially in determining of crystalline structures and solid samples.
X-rays are a type of electromagnetic radiation with an energy far superior to the ultraviolet radiation that allows its absorption by the core electrons. X-rays are especially capable of penetrating crystalline structures: their wavelength, of an order of magnitude equal to that of interatomic distances. Spectroscopic X-ray techniques
The absorption, emission, fluorescence and dispersion of X-rays are used in many spectroscopic techniques that provide us with information on the structure and composition of the matter:
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