X-ray diffraction crystallography

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X-ray diffraction crystallography A method of analysis in which an X-ray beam of known wavelength is directed at a crystal, and the beam is diffracted by reflections off planes of atoms in the crystal. By recording the angular positions of diffracted beams, the spacing between atomic planes can be determined according to the Bragg equation, nλ = 2d sinθ (see BRAGG'S LAW). The procedure is repeated for various directions in the crystal and a model of its internal structure established. In geology, the technique is used to identify minerals.

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