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The Rietveld method fits a calculated profile (including all structural and instrumental parameters) to experimental data. It employs the non-linear least squares method, and requires the reasonable initial approximation of many free parameters, including peak shape, unit cell dimensions and coordinates of all atoms in the crystal structure.
The use of computational methods for the powder X-ray diffraction data analysis is now generalized. It typically compares the experimental data to the simulated diffractogram of a model structure, taking into account the instrumental parameters, and refines the structural or microstructural parameters of the model using least squares based ...
ENDOR – Electron nuclear double resonance, see ESR or EPR; EPMA – Electron probe microanalysis; EPR – Electron paramagnetic resonance spectroscopy; ERD or ERDA – Elastic recoil detection or elastic recoil detection analysis; ESCA – Electron spectroscopy for chemical analysis see XPS; ESD – Electron stimulated desorption
X-ray diffraction computed tomography is an experimental technique that combines X-ray diffraction with the computed tomography data acquisition approach. X-ray diffraction (XRD) computed tomography (CT) was first introduced in 1987 by Harding et al. [ 1 ] using a laboratory diffractometer and a monochromatic X-ray pencil beam .
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 .
Modern advances in nuclear and radiochemistry research have allowed practitioners to apply chemistry and nuclear procedures to elucidate nuclear properties and reactions, used radioactive substances as tracers, and measure radionuclides in many different types of samples.
One drawback of many configurations is that the sample must be moved in order to use other surface analysis methods such as LEED or AES, and after moving the sample back into the X-ray diffraction position, it must be realigned. In some setups, the sample chamber can be detached from the diffractometer without breaking vacuum, allowing for ...
Surface X-ray diffraction (SXRD), which is similar to RHEED but uses X-rays, and is also used to interrogate surface structure. [3] X-ray standing waves, another X-ray variant where the intensity decay into a sample from diffraction is used to analyze chemistry. [4]