The Fine Structure Before and After Each Edge

The Fine Structure Before and After Each Edge. ELNES is the term use to describe the energy-loss near edge structure, and this can be quite different for an element in different compounds. For example the shape of the aluminium L edges are quite different in EELS spectra from metallic aluminium and aluminium oxide, so that the chemical form of a given element may be indentified from these small variations in intensity after the edge. [Pg.191]

EXELFS (the extended energy-loss fine structure) carries information about the bonding and co-ordination of the atoms contributing to the edge. However, the signal needs to be strong before statistically reliable information can be obtained. [Pg.191]

These authors produced TEM samples of Bi-doped, Sb-doped and Ag-doped copper foils, thinned to electron transparency using conventional preparation procedures. In all cases the presence of impurity segregation was confirmed using conventional X-ray energy-dispersive spectrometry. The EELS measurements were carried out with a STEM operating at 100 keV, with a nominal probe size of 1 nm (full width at half maximum) with a current of about 0.5 nA. The conditions required to optimize detection sensitivity for interface analysis require the highest current density and are not consistent with achieving the smallest probes. [Pg.191]

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