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Bragg's Law & X-ray Diffraction Animation

Bragg’s law gives the condition for the maximum intensity of the diffracted X-ray and the details about the crystal lattice. X-rays, discovered by Wilhelm Roentgen in 1895, are electromagnetic waves of very short wavelength (of the order of 0.1 nm). It would be impossible to get a grating having such a small spacing. However, the atomic spacing in a crystal is known to be about 0.1 nm. When a monochromatic X-rays are incident upon a crystal, atoms in different layers acts as a source of scattering radiation of same wavelength. The intensity of the reflected beam will be maximum at certain incident angle when the path difference between two reflected wave from two different planes is an integral multiple of wavelength of X-rays. A crystal is considered to be composed of series of parallel and equidistance plane. Lawrence Bragg thought of each plane of atoms in a crystal as a reflecting surface. The X-rays would hit each plane of atoms in turn, reflecting first off the surface layer, then the one below it, and so on. If the X-rays reflected off all the surfaces were in phase, with their peaks and troughs all aligned, then a very strong signal could be measured from the reflection. Hep Cats by Kevin MacLeod is licensed under a Creative Commons Attribution license (https://creativecommons.org/licenses/...) Source: http://incompetech.com/music/royalty-... Artist: http://incompetech.com/