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A broad spectrum of X-rays (that is, a blend of X-rays with different wavelengths) can also be used to carry out X-ray diffraction, a technique known as the Laue method. This is the method used in the original discovery of X-ray diffraction.
X-ray diffraction, sometimes called Wide-angle X-ray diffraction (WAXD) Small-angle X-ray scattering (SAXS) probes structure in the nanometer to micrometer range by measuring scattering intensity at scattering angles 2θ close to 0°. X-ray reflectivity is an analytical technique for determining thickness, roughness, and density of single layer ...
Typically, powder X-ray diffraction (XRD) is an average of randomly oriented microcrystals that should equally represent all crystal orientation if a large enough sample is present. X-rays are directed at the sample while slowly rotated that produce a diffraction pattern that shows intensity of x-rays collected at different angles. Randomly ...
X-ray optics is the branch of optics dealing with X-rays, rather than visible light.It deals with focusing and other ways of manipulating the X-ray beams for research techniques such as X-ray diffraction, X-ray crystallography, X-ray fluorescence, small-angle X-ray scattering, X-ray microscopy, X-ray phase-contrast imaging, and X-ray astronomy.
Small-angle X-ray scattering (SAXS) is a small-angle scattering technique by which nanoscale density differences in a sample can be quantified. This means that it can determine nanoparticle size distributions, resolve the size and shape of (monodisperse) macromolecules, determine pore sizes and characteristic distances of partially ordered materials. [1]
It is an X-ray-diffraction [2] method and commonly used to determine a range of information about crystalline materials. The term WAXS is commonly used in polymer sciences to differentiate it from SAXS but many scientists doing "WAXS" would describe the measurements as Bragg/X-ray/powder diffraction or crystallography.
Today, selenium-SAD is commonly used for experimental phasing due to the development of methods for selenomethionine incorporation into recombinant proteins. SAD is sometimes called "single-wavelength anomalous dispersion" , but no dispersive differences are used in this technique since the data are collected at a single wavelength.
X-ray diffraction topography is one variant of X-ray imaging, making use of diffraction contrast rather than absorption contrast which is usually used in radiography and computed tomography (CT). Topography is exploited to a lesser extent with neutrons , and is the same concept as dark field imaging in an electron microscope .