X-ray adsorption fine-structure

Schertel A, Hahner G, Grunze M and Well C 1996 Near edge x-ray adsorption fine structure investigation of the... 

Elder, R.C., Tepperman, K.G., Eidsness, M.K., Heeg, M.J., Shaw, C.F. Ill and Schaeffer, N. A. (1983) Gold-based antiarthritic drugs and metabolites. Extended x-ray adsorption fine structure (EXAFS) spectroscopy and x-ray absorption near edge spectroscopy (XANES). ACS Symposium Series, 209, 385-400. 

X-ray absorption spectroscopy (XAS) Methods that use X-rays to investigate the physical and chemical properties of materials on an atomic scale. XAS includes X-ray adsorption fine structure (XAFS) spectroscopy and its X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra. 

HREELS108 and surface extended X-ray adsorption fine structure (SEXAFS)109 measurements reveal that Si—O—Si complexes exist in the early stage of oxidation. Based on... 

NEXAFS Near-Edge X-ray Adsorption Fine Structure... 

A few structures have been solved by x-ray adsorption near-edge fine structure (XANES), including oxygen on Ni(100)./16/ This technique is also known as near-edge x-ray adsorption fine structure (NEXAFS). 

A number of different experimental methods are available to observe fine structure. In extended x-ray adsorption fine structure (EXAFS) experiments x-ray photons excite core levels and the cross section is determined by x-ray absorption... 

Direct in situ extended X-ray adsorption fine structure (EXAFS) measurements) from synchrotron radiation (14-18) permit the determination of species adsorbed to neighboring ions and to central ions on oxide surfaces in the presence of water. Such investigations showed, for example, that selenite is bound in an inner-sphere complex and selenate is bound in an outer-sphere complex to the central Fe(III) ions of a goethite surface. This technique also showed that Pb(II) is bound in an inner-sphere complex to 8-Al203 (19) and that Cr(III) is bound in an inner-sphere complex at the oxide-water interface of Mn(IV) oxides and ferric hydrous oxides (17, 18). 

X-Ray Adsorption Fine Structure Data Collection and Analysis... 

Metallic sites Temperature-programmed reduction (TPR) X-ray adsorption near-edge spectroscopy (XANES) Extended X-ray adsorption fine structure (EXAFS) Mossbauer spectroscopy X-ray photoelectron spectroscopy (XPS) Electron paramagnetic spectroscopy (EPR)... 

Schertel A, Hahner G, Grunze M and Wdll C 1996 Near edge x-ray adsorption fine structure investigation of the orientation and thermally induced order-disorder transition in thin organic films containing long chain hydrocarbons J. Vac. Sci. Technol. A 14 1801-6... 

Hydroformylation of ethylene was catalyzed by the cluster anion [Ru5G(GO)i6Me] , supported on a highly dehydrated silica (823 K). The catalysis was nearly 100% selective at 398 K. The retention of the cluster framework under the reaction conditions was shown by extended X-ray adsorption fine-structure curve fitting. The cluster anion does not catalyze this reaction in homogeneous solution, and a heterogeneous Ru-SiOz catalyst prepared by conventional methods gave ethane rather than propanal. "... 

Okada and Haroda [25] studied the local structures of chloride and bromide within an anion-exchange resin by means of X-ray adsorption fine structure (XAFS). Water molecules are coordinated with the paired anion within the resin, up to an average hydration number of 3. However, the anions are not as highly hydrated within the resin as they are in the external solution. An average of 2.1 water molecules are stripped off in transfer of chloride from the bulk solution to the resin. An average of 2.6 water molecules are stripped off bromide in the same transfer. 

NEXAFS is generally characterized by spectral features near to an X-ray absorption edge and contains information about the electronic and structural properties of the adsorbing atom. This is distinct from the extended X-ray adsorption fine structure (EXAFS), which is typically observed in the region 50-1000eV above an... 

---