X-ray Absorption Fine Structure XAFS

HexOMe, methyl glycoside Hex-onic, aldohexonic acid hmba, 2-hydroxy-2-methylbutanoate2 HYSCORE, hyperfine sublevel correlation spectroscopy mod. ampl., modulation amphtude polyGalA, galacturonan Qa, quinic acid XAFS, X-ray absorption fine structure spectroscopy... 

Abbreviations CCD, charge-coupled device DEXAFS, dispersive extended X-ray absorption fine structure EXAFS, extended X-ray absorption fine structure QEXAFS, quick extended X-ray absorption fine structure TPR, temperature-programmed reaction XRD, X-ray diffraction XAFS, X-ray absorption fine structure. 

Direct methods for studying the structure of molten salts are X-ray and neutron diffraction analyses, infrared and Raman spectroscopy, NMR (nuclear magnetic resonance) measurement, and also very recently, XAFS (X-ray Absorption Fine Structure) measurement in melts, were developed. Fiowever, the most frequently used direct methods are X-ray and XAFS measurements, Raman spectroscopy, and NMR measurements. Therefore these three methods of direct investigation will be briefly described here. 

X-ray diffraction and XAFS (X-ray Absorption Fine Structure) measurements are powerful techniques to investigate the local atomic structure of solid and liquid phases and have been successfully applied to many types of materials such as solutions, catalysts, amorphous solids, etc. However, the X-ray diffraction and XAFS measurement of molten salts bring a number of common difficulties due to high temperature and their specific properties, as in the experimental work. 

Acronyms XAFS X-ray absorption fine structure, EXAFS extended X-ray absorption fine structure, XANES X-ray absorption near edge spectroscopy, (XAFS includes both EXAFS and XANES). 

One of the new fields of actinide chemistry since the 1990s is an application of X-ray absorption spectroscopy (Teo 1986) especially by use of the synchrotron radiation. XAFS (X-ray absorption fine structure) is a powerful technique for characterization of the local structure of specific elements, even radioactive elements such as actinides, and their electronic states. XAFS contains two fundamental information, EXAFS (extended X-ray absorption fine structure) and XANES (X-ray absorption near-edge structure). O Figure 18.27 shows a fundamental pictorial view of the XAFS process (Koningsberger and Prins 1987). 

PMO Perturbative Molecular Orbital XAFS X-Ray Absorption Fine Structure... 

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