Extended X-ray fine structure

Extended x-ray fine structure spectroscopy (EXAFS, Synchrotron) (Bowron et al., 1998)... 

In this Chapter, we focus on alkali-aluminum surface alloys where the geometrical structure has been determined in detail. As can be seen from Table 1, which contains a list of the adsorbed phases formed by adsorption of alkali metals on aluminium surfaces, this limitation is not a serious restriction, since studies exist for a quite a number of low index aluminum surfaces and alkali metals. Although most of the structures of the phases listed in Table 1 have been determined by low energy electron diffraction (LEED), the crucial, first observation of substitutional adsorption for alkali-aluminium systems was made in a combined surface extended x-ray fine structure (SEXAFS) and density functional theory (DFT) study of the Al(l 11)—(v 3 x 3)7 30°—Na phase formed by adsorption of 1/3 ML Na at room temperature by Schmalz et al [7] in 1991. The structure of the Al(lll)-(4 x 4)—Na phase was also determined by SEXAFS. 

Extended x-ray fine structure analysis can determine the identity, coordination number, and distance of atoms surrounding a given element. 

EPR = Electron paramagnetic resonance EXAFS = Extended X-ray fine structure analysis ESEEM = Electron spin echo envelope spectroscopy XANES = X-ray absorption near edge structure analysis NMR = Nuclear magnetic resonance. 

Extended x-ray fine structure EXAFS varies Chemical states Low Oscill. in x-ray Slow 121, 122... 

For PSM processes that involve introduction or exchange of metal centers, a range of spectroscopic techniques have been used to provide evidence of the metal centers and their environments. These include atomic absorption spectroscopy (AAS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy, and extended X-ray fine structure (EXAFS) spectroscopy. ... 

AAS = atomic absorption spectroscopy ATOF-MS = aerosol time-of-flight mass spectrometry 2,6-ndc = 2,6-naphthalenedicarboxylate bdc = 1,4-benzenedicar-boxylate bpdc = 1,3,5-benzenetricarboxylate bpydc = 2,2 -bipyridine-5,5 -dicarboxylate btb = 4,4, 4"-benzene-1,3,5-triylbenzoate btc = 1,3,5-benzenetricarboxylate 3D = three-dimensional dabco = l,4-diaza[2.2.2]bicyclo-octane EDX = energy-dispersive X-ray spectroscopy EXAFS = extended X-ray fine structure Fc = ferrocenyl ICP-AES = inductively coupled plasma atomic emission spectroscopy MOF = metal-organic framework PSD = postsynthetic deprotection PSM = Postsynthetic modification PXRD = Powder X-ray diffraction 1,4-ndc = 1,4-naphthalenedicarboxylate SALE = solvent-assisted linker exchange SBU = secondary building unit ... 

Glancing Angle X-Ray Diffraction Appearance Potential Extended X-Ray Fine Structure... 

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