Extended X-ray Energy Loss Fine

EXELFS Extended X-ray Energy Loss Fine Structure A fine-structure technique similar to EXAFS, except that 60-300 KeV electrons rather than photons excite core-holes. Like EXAFS, this techniques is not explicitly surface sensitive. 

Extended X-Ray Energy Loss Fine Structure (EXELFS)... 

EXELFS Extended X-ray energy loss fine structure... 

Extended energy-loss fine structures (EXELES) are analogous to the EXAES effect observed in X-ray absorption [2.224, 2.225]. These weak modulations (cf Eig. 2.39a), still observable ca. 100 eV away from the edge onset, occur because the excited elec-... 

Diffuse reflectance infrared Fourier transform spectroscopy deuterium triglycine sulphate energy compensated atom probe energy dispersive analysis energy-loss near edge structure electron probe X-ray microanalysis elastic recoil detection analysis (see also FreS) electron spectroscopy for chemical analysis extended energy-loss fine structure field emission gun focused ion beam field ion microscope... 

Table 5.2 Summary of selected analytical methods for molecular environmental geochemistry. AAS Atomic absorption spectroscopy AFM Atomic force microscopy (also known as SFM) CT Computerized tomography EDS Energy dispersive spectrometry. EELS Electron energy loss spectroscopy EM Electron microscopy EPR Electron paramagnetic resonance (also known as ESR) ESR Electron spin resonance (also known as EPR) EXAFS Extended X-ray absorption fine structure FUR Fourier transform infrared FIR-TEM Fligh-resolution transmission electron microscopy ICP-AES Inductively-coupled plasma atomic emission spectrometry ICP-MS Inductively-coupled plasma mass spectrometry. Reproduced by permission of American Geophysical Union. O Day PA (1999) Molecular environmental geochemistry. Rev Geophysics 37 249-274. Copyright 1999 American Geophysical Union...

P.R. Watson. Critical Compilation of Surface Structures Determined by Surface Extended X-Ray Absorption Fine Stmcture (SEXAFS) and Surface Extended Electron Energy Loss Spectroscopy (SEELFS). J. Pins. Chem. Ref Data 21 123 (1992). 

The experimental detection and quantification of surface species on in situ soil particles and other natural colloids is a difficult area of research because of sample heterogeneity, low surface concentrations, and the necessity of investigating the solid adsorbents in the presence of water. Unambiguous information can be obtained only with in situ surface spectroscopy, such as X-ray photoelectron (XPS), extended X-ray absorption fine structure (EXAFS), X-ray absorption near edge structure (XANES), inelastic electron tunnelling (lETS), and electron energy loss (EEL) spectroscopies. Recent advances in the development of non-invasive, in situ spectroscopic scanned-probe and microscopic techniques have been applied successfully to study mineral particles in aqueous suspensions (Hawthorne, 1988 Hochella and White, 1990 Bertsch and Hunter, 1998). 

The usefulness of X-ray absorption spectroscopies in zeolite research, i.e. extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES), as well as electron energy loss spectroscopy and resonant X-ray diffraction is demonstrated by P. Behrens (Chapter 5) and illustrated by a niunber of interesting examples, e.g., the EXAFS of manganese-exchanged A- and Y-type zeoHtes and guest-containing molecular sieves, or the XANES of oxidation states of non-framework species. 

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