Core-level electron energy loss spectroscopy

Core damage frequency (CDF), for nuclear power facilities, 17 540 Coreless induction furnaces, 12 309-311 Core level electron energy loss spectroscopy (CEELS), 24 74 Coremans, Paul, 11 398 Core-shell model, 14 464 Core-shell particles, in polymer blends, 20 354-355... 

Xeels = electron energy loss spectroscopy. y hreels = high resolution electron energy loss spectroscopy. Z ceels = core level electron energy loss spectroscopy. aaesdiad = electron-stimulated ion angular distribution. 

CEELS core-level electron energy-loss spectroscopy... 

The electron-energy-loss spectroscopy (EELS) was performed in transmission with a primary beam energy of 170 keV in a purpose-built UHV spectrometer described in detail elsewhere [5]. For the valence level excitations and elastic scattering (electron diffraction) data the momentum resolution of the instrument was set to 0.04 A 1 with an energy resolution of 90-140 meV. The core level excitations were performed with a momentum and energy resolution of 0.2 A"1 and 90-140 meV, respectively. All EELS experiments were conducted at room temperature. 

Muller DA, Batson PE, Silcox J (1998) Measurement and models of electron-energy-loss spectroscopy core-level shifts in nickel aluminum intermetallics. Phys Rev B 58 11970... 

The core loss structure in electron energy loss spectroscopy (EELS) is known to be very similar to XANES, because the core loss spectrum is caused by physically the same process as that of x-ray absorption, corresponding to the electronic transition from core level to unoccupied excited states. Therefore, the theoretical analysis for ELNES can be carried out by almost the same procedure used for that of XANES. For the chemical state analysis of oxide ceramics, ELNES has also been proved to be very efficient with theoretical analysis by DV-Xa cluster calculation . The cluster calculation indicates that the core-hole effect due to the electronic transition is sometimes very important and the ground state calculation gives a serious errors in excited electronic state. 

Another technique used for the study of core level excitation is electron energy loss spectroscopy (EELS). Experimentally an electron beam is incident on a target and the energy loss of the reflected or transmitted electrons is analyzed. 

Fig. 4. Schematic representation of the principle of the different core level spectroscopies. Lower part (See caption of fig. 3.) (a) and (b) SXE soft X-ray emission, (a) and (c) AES Auger electron spectroscopy, (d) XPS X-ray photoemission spectroscopy, (e) SXA soft X-ray absorption, (f) EELS electron energy loss spectroscopy. Upper part (See caption of fig. 3.) Half-filled rectangle excited final state with the same electron count as in the initial state, (e), (f). Divided rectangle final state with two electrons less than in the initial state (see also fig. 19b).

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