Extended X-ray absorption spectroscopy

EXAFS Extended X-ray absorption spectroscopy FT Fourier transform... 

Two techniques capable of positive identification of both the vanadyl and the vanadium(III) oxidation states are extended X-ray absorption spectroscopy (EXAS) and magnetic susceptibility. EXAS experiments on A. ceratodes yield approximately 95% V(III) and 5% V(IV) (148). A similar distribution, 90% V(III) and 10% V(IV), was found for A. nigra using a superconducting quantum interference device to measure magnetic susceptibility (149). 

Stumpf S, Billard 1, Gaillard C, et al. Time-resolved laser fluorescence spectroscopy and extended X-ray absorption spectroscopy investigations of the N3 complexation of Eu(III), Cm(III), and Am(III) in an ionic liquid Differences and similarities. Inorg. Chem. 2008. 47, 4618-4626. 

For XANES, a narrow energy range (< 50 eV) close to the absorption edge is studied. However, for extended X-ray absorption spectroscopy (EXAFS) the spectrum is acquired at energies much further from the absorption edge. Information... 

Different characterization techniques are used to get an insight into the location of transition metal ions in an aluminophosphate framework. Generally, the data on the cation location are collected with difficulty since the metal concentration is low. In this regard, it is necessary to use more than one method if a reliable conclusion is to be reached (ie, the simultaneous application of several physical techniques is recommended). The following characterization methods are commonly applied diffuse reflectance UV-vis spectroscopy (DRS), electron spin resonance (ESR), electron spin echo modulation (ESEM), infrared (IR), and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopies, as well as the nuclear magnetic resonance spectroscopy (NMR), Mossbauer spectroscopy and the X-ray absorption near-edge spectroscopy (XANES) and extended X-ray absorption spectroscopy for fine structure (EXAFS) (167,168) and references therein). 

Another technique that makes use of the tuneability of SR sources is x-ray absorption spectroscopy (xas) (2). This is relatively rarely used in pol5uner research. One of the few examples found in the literature deals with halato-telechelic ionomers (40). These are short linear chains selectively terminated by a metal car-boxylate or sulfonate ionic group. The local order of these groups could be determined by using extended x-ray absorption spectroscopy (exafs). More work using this technique applied to ionomer morphology is reported (41). 

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