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  2. Scherrer equation - Wikipedia

    en.wikipedia.org/wiki/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.

  3. R-factor (crystallography) - Wikipedia

    en.wikipedia.org/wiki/R-factor_(crystallography)

    The minimum possible value is zero, indicating perfect agreement between experimental observations and the structure factors predicted from the model. There is no theoretical maximum, but in practice, values are considerably less than one even for poor models, provided the model includes a suitable scale factor.

  4. Rietveld refinement - Wikipedia

    en.wikipedia.org/wiki/Rietveld_refinement

    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 ...

  5. Extended X-ray absorption fine structure - Wikipedia

    en.wikipedia.org/wiki/Extended_X-ray_absorption...

    The dominant physical process in x-ray absorption is one where the absorbed photon ejects a core photoelectron from the absorbing atom, leaving behind a core hole. [1] The ejected photoelectron's energy will be equal to that of the absorbed photon minus the binding energy of the initial core state. The atom with the core hole is now excited and ...

  6. X-ray crystallography - Wikipedia

    en.wikipedia.org/wiki/X-ray_crystallography

    An X-ray diffraction pattern of a crystallized enzyme. The pattern of spots (reflections) and the relative strength of each spot (intensities) can be used to determine the structure of the enzyme. The relative intensities of the reflections provides information to determine the arrangement of molecules within the crystal in atomic detail.

  7. X-ray diffraction - Wikipedia

    en.wikipedia.org/wiki/X-ray_diffraction

    A regular array of scatterers produces a regular array of spherical waves. Although these waves cancel one another out in most directions through destructive interference, they add constructively in a few specific directions. [21] [22] [23] An intuitive understanding of X-ray diffraction can be obtained from the Bragg model of diffraction. In ...

  8. Wide-angle X-ray scattering - Wikipedia

    en.wikipedia.org/wiki/Wide-angle_X-ray_scattering

    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 ...

  9. Wavelength-dispersive X-ray spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Wavelength-dispersive_X...

    This is compared with reference spectra to determine the elemental composition of the sample. [2] As the atomic number of the element increases so there are more possible electrons at different energy levels that can be ejected resulting in x-rays with different wavelengths. This creates spectra with multiple lines, one for each energy level.