![]() Copper is the most common target material for single-crystal diffraction, with CuK α radiation = 1.5418 Å. K α1and K α2 are sufficiently close in wavelength such that a weighted average of the two is used. Filtering, by foils or crystal monochrometers, is required to produce monochromatic X-rays needed for diffraction. The specific wavelengths are characteristic of the target material (Cu, Fe, Mo, Cr). K α1 has a slightly shorter wavelength and twice the intensity as K α2. ![]() These spectra consist of several components, the most common being K α and K β. When electrons have sufficient energy to dislodge inner shell electrons of the target material, characteristic X-ray spectra are produced. X-rays are generated in a cathode ray tube by heating a filament to produce electrons, accelerating the electrons toward a target by applying a voltage, and bombarding the target material with electrons. Typically, this is achieved by comparison of d-spacings with standard reference patterns.īruker's X-ray Diffraction D8-Discover instrument. Conversion of the diffraction peaks to d-spacings allows identification of the mineral because each mineral has a set of unique d-spacings. By scanning the sample through a range of 2 θangles, all possible diffraction directions of the lattice should be attained due to the random orientation of the powdered material. These diffracted X-rays are then detected, processed and counted. ![]() This law relates the wavelength of electromagnetic radiation to the diffraction angle and the lattice spacing in a crystalline sample. The interaction of the incident rays with the sample produces constructive interference (and a diffracted ray) when conditions satisfy Bragg's Law ( n λ=2 d sin θ). ![]() These X-rays are generated by a cathode ray tube, filtered to produce monochromatic radiation, collimated to concentrate, and directed toward the sample. ![]() X-ray diffraction is based on constructive interference of monochromatic X-rays and a crystalline sample. ![]()
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