Search results
Results from the WOW.Com Content Network
XAS methodology can be broadly divided into four experimental categories that can give complementary results to each other: metal K-edge, metal L-edge, ligand K-edge, and EXAFS. The most obvious means of mapping heterogeneous samples beyond x‐ray absorption contrast is through elemental analysis by x‐ray fluorescence, akin to EDX methods in ...
This results in an absorption edge. Every element has a set of unique absorption edges corresponding to different binding energies of its electrons, giving XAS element selectivity. XAS spectra are most often collected at synchrotrons because the high intensity of synchrotron X-ray sources allows the concentration of the absorbing element to ...
One peak is from the L shell of iron. Energy-dispersive X-ray spectroscopy ( EDS , EDX , EDXS or XEDS ), sometimes called energy dispersive X-ray analysis ( EDXA or EDAX ) or energy dispersive X-ray microanalysis ( EDXMA ), is an analytical technique used for the elemental analysis or chemical characterization of a sample .
X-ray absorption edge spectroscopy corresponds to the transition from a core-level to an unoccupied orbital or band and mainly reflects the electronic unoccupied states. EXAFS, resulting from the interference in the single scattering process of the photoelectron scattered by surrounding atoms, provides information on the local structure.
TGA – Thermogravimetric analysis; TIKA – Transmitting ion kinetic analysis; TIMS – Thermal ionization mass spectrometry; TIRFM – Total internal reflection fluorescence microscopy; TLS – Photothermal lens spectroscopy, a type of photothermal spectroscopy; TMA – Thermomechanical analysis; TOF-MS – Time-of-flight mass spectrometry
Analysis of the X-ray emission spectrum produces qualitative results about the elemental composition of the specimen. Comparison of the specimen's spectrum with the spectra of samples of known composition produces quantitative results (after some mathematical corrections for absorption, fluorescence and atomic number).
Absorption attenuates the secondary X-rays leaving the sample. For example, the mass absorption coefficient of silicon at the wavelength of the aluminium Kα line is 50 m 2 /kg, whereas that of iron is 377 m 2 /kg. This means that fluorescent X-rays generated by a given concentration of aluminium in a matrix of iron are absorbed about seven ...
X-ray absorption near edge structure (XANES), also known as near edge X-ray absorption fine structure (NEXAFS), is a type of absorption spectroscopy that indicates the features in the X-ray absorption spectra of condensed matter due to the photoabsorption cross section for electronic transitions from an atomic core level to final states in the energy region of 50–100 eV above the selected ...