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X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract in specific directions. By measuring the angles and intensities of the X-ray diffraction, a crystallographer can produce a three-dimensional picture of ...
X-ray diffraction is a generic term for phenomena associated with changes in the direction of X-ray beams due to interactions with the electrons around atoms. It occurs due to elastic scattering, when there is no change in the energy of the waves. The resulting map of the directions of the X-rays far from the sample is called a diffraction pattern.
In X-ray crystallography, wide-angle X-ray scattering (WAXS) or wide-angle X-ray diffraction (WAXD) is the analysis of Bragg peaks scattered to wide angles, which (by Bragg's law) are caused by sub-nanometer-sized structures. [1] It is an X-ray-diffraction [2] method and commonly used to determine a range of information about crystalline materials.
Rietveld refinement is a technique described by Hugo Rietveld for use in the characterisation of crystalline materials. The neutron and X-ray diffraction of powder samples results in a pattern characterised by reflections (peaks in intensity) at certain positions. The height, width and position of these reflections can be used to determine many ...
X-ray filters are also used for X-ray diffraction, in determinations of the interatomic spaces of crystalline solids. These lattice spacings can be determined using Bragg diffraction, but this technique requires scans to be done with approximately monochromatic X-ray beams. Thus, filter set ups like the copper nickel system described above are ...
X-ray reflectivity is an analytical technique for determining thickness, roughness, and density of single layer and multilayer thin films. Wide-angle X-ray scattering (WAXS), a technique concentrating on scattering angles 2θ larger than 5°. Spectrum of various inelastic scattering processes that can be probed with inelastic X-ray scattering ...
Scherrer equation. The Scherrer equation, in X-ray diffraction and crystallography, is a formula that relates the size of sub- micrometre crystallites in a solid to the broadening of a peak in a diffraction pattern. It is often referred to, incorrectly, as a formula for particle size measurement or analysis.
Characteristic X-ray spectroscopy. When an electron from the inner shell of an atom is excited by the energy of a photon, it moves to a higher energy level. When it returns to the low energy level, the energy it previously gained by excitation is emitted as a photon of one of the wavelengths uniquely characteristic of the element.