X-ray absorption fine structure (XAFS) provides information on the atomic-scale structure around a specific atom, and has become an essential analytical tool in materials, biology and many other sciences [1, 2]. The availability of a synchrotron source has facilitated the application of XAFS, because a strong smooth spectral distribution is important for the measurements, and synchrotron radiat...

X-ray-absorption ne structure (XAFS) data of RbBr, RbCl and KBr at 30 K and 125 K were measured and analysed. An ionized atom multiple-scattering (MS) calculation and a correlated Debye model were used for tting FEFF5 theory to data. The modiications of FEFF5 necessary to obtain good ts to the data are discussed. The results demonstrate the domination of single-scattering and focusing paths in ...

A new theoretical approach and computational package, FDMX, for general calculations of X-ray absorption fine structure (XAFS) over an extended energy range within a full-potential model is presented. The final-state photoelectron wavefunction is calculated over an energy-dependent spatial mesh, allowing for a complete representation of all scattering paths. The electronic potentials and corres...

Transport behavior of '37Cs in the environment is regulated by surface sorption reactions on clay mineral surfaces. To provide greater understanding of Cs transport processes, XAFS investigations of the local environments of 133Cs sorbed to clay minerals were conducted on Cs-Ca exchanged clay suspensions at the Cs LIII-edge. With decreased surface loadings of Cs, the Cs local environment exhibi...

A new approach is introduced for determining X-ray absorption spectroscopy (XAS) spectra on absolute and relative scales using multiple solutions with different concentrations by the characterization and correction of experimental systematics. This hybrid technique is a development of standard X-ray absorption fine structure (XAFS) along the lines of the high-accuracy X-ray extended range techn...

A direct an accurate technique for calculating the thermal X-ray absorption fine structure (XAFS) DebyeWaller factors (DWF) for materials of crystalline structure is presented. Using the Density Functional Theory (DFT) under the hybrid X3LYP functional, a library of MnO spin–optimized clusters are built and their phonon spectrum properties are calculated; these properties in the form of normal ...

The activation of the ethene tetramerisation catalyst system based upon [CrCl3(THF)3] and N( Pr)(PPh2)2 has been investigated in situ via the reaction of [CrCl3{PPh2N(R)PPh2}(THF)] 1a (R = Pr) with excess AlMe3 in toluene. The Cr K-edge XAFS spectrum of the solution freeze quenched after 1 min reaction time indicated monomethylation of the metal with the resultant product being [CrClMe(ClAlCl3)...

The production of high-energy (1 KeV to 40 KeV) x-radiation at synchrotron laboratories around the world has enabled the spectroscopic analysis of core level electronic transitions and electronic scattering processes in trace (< 1000 ppm) metal and metalloid atoms as they are found in heterogeneous natural materials (e.g., soils, sediments, plants, and microbial mats). Environmental geochemists...