Electron energy loss spectra

Fig. VIII-10. (a) Intensity versus energy of scattered electron (inset shows LEED pattern) for a Rh(lll) surface covered with a monolayer of ethylidyne (CCH3), the structure of chemisorbed ethylene, (b) Auger electron spectrum, (c) High-resolution electron energy loss spectrum. [Reprinted with permission from G. A. Somoijai and B. E. Bent, Prog. Colloid Polym. ScL, 70, 38 (1985) (Ref. 6). Copyright 1985, Pergamon Press.]...

Cox, P. A., EgdeD, R. G., Eriksen, S. and Elavell, W. R. (1986) The high-resolution electron-energy-loss spectrum of TiO2(110)./. Electron Spectrosc. Relat. Phenom., 39, 117-126. 

Figure 10. Electron energy loss spectrum corresponding to Figure 9a. a, Si2, b, and c indicate the four energy windows 272-277 eV, 277-282 eV, 282-287 eV, and 287-292 eV, respectively.

Pb(110) at 77 K and warming to 140 K with (b) electron energy loss spectrum confirming the presence of surface hydroxyls at 160K when molecularly adsorbed water has desorbed. Both the oxide overlayer at Pb(110) and the atomically clean surface are unreactive to water. H abstraction was effected by transient Os states, which were also active in NH3 oxidation. (Reproduced from Refs. 40, 42). 

Figure 5.40. Illustration of an electron energy-loss spectrum showing the three typical regions a zero-loss peak, a low-loss peak and L and K edges.

Figure 5.45. Electron energy loss spectrum of MoNi-5 precipitate showing the Ni L23 edge at 855 eY. (Reproduced with permission of Penisson and Yystavel 2000.)...

Figure 11. Electron-energy-loss spectrum of crystalline boron nitride, showing the boron K-edge (at 190 eV) and the nitrogen K-edge (at 400 eV). The background intensity, delineated by the dashed curve arises from inelastic scattering by valence electrons. The hatched areas represent the measured values required for the quantitative analysis of boron ( see text) (50).

Fig. 12. Electron energy-loss spectrum of uranophane solids containing 1300 and 6300 ppm Np. The double arrows on the figure are 176 eV and 184 eV wide, demonstrating the presence of Np in the solid (extracted from Buck et aL 2003).

No UV absorption studies of [1.1.1 Jpropellane seem to have been reported, but a recent measurement of the electron energy loss spectrum provided a wealth of information about the electronically excited states of this molecule23. 

Figure 5. Schematic diagram of 2.5-keV electron energy-loss spectrum of CF4.

Hunt, J. A., and Williamds, D. B. (1991). Electron energy-loss spectrum-imaging. Ultramicr. 38,47-73. 

French, R.H., Miillejans, H., Jones, D.J., Duscher, G., Cannon, R.M. and Ruhle, M. (1998), Dispersion forces and Hamaker constants for intergranular films in silicon nitride from spatially resolved-valence electron energy loss spectrum imaging , Acta Mater., 46 (7), 2271-2287. 

Figure 1. Electron energy-loss spectrum of GdBa C O illustrating the various observable types of fine structures a) the low-loss segment including the outer shell ionization edges b) the innershell core-loss edges the background model AE r and the parameters used in microanalysis (IA, ea. A) are also shown.

FIGURE 13 Graded oxide nanoparticle. Mo02 was oxidized with air at 723 K to give a core-shell structure of molybdenum dioxide and possibly molybdenum trioxide that was identified by its different electron energy loss spectrum. No structural description of the highly disordered and catalytically relevant outer oxide shell could be determined, either with XRD or with TEM, (or even with EXAFS spectroscopy) as the signals are dominated by the core structure. 

Additional information on the vibrations of [l.l.ljpropellane was obtained from the analysis of its electron energy loss spectrum l... 

Figure 23 High-resolution electron energy-loss spectrum of CO adsorbed at different coverages on Rh(l 11)...

Underhill, P. R., and T. E. Gallon (1982). The surface defect peak in the electron energy loss spectrum of MgO (100). Solid State Commun. 43, 9-II. 

For comparison with experimental data [100-102], it is common to evaluate the oscillator strengths, photo absorption cross section and EELS (Electron Energy Loss Spectrum) defined here in terms of the imaginary part of the polarizability 7 ... 

Fig. 1. Electron energy loss spectrum of propane (thin line) and the calculated spectrum (thick line) for the incident electron energy of 10 eV and the scattering angle of 100°. The bars at the bottom of the figure stand for the calculated differential cross sections.

As demonstrated by the results presented above, the probability of dissociative chemisorption can be readily probed by measuring the extent of carbon deposition by Auger electron spectroscopy. However, a complete picture of the dissociative adsorption process requires that the product of the dissociative chemisorption event be spectroscopically identified. For example, although the discussion has assumed that a single C-H bond cleaves upon dissociation, no evidence for this has been presented. In order to identify chemically the product of the dissociative chemisorption event, we have measured the high resolution electron energy loss spectrum for methane deposited on the Ni(lll) surface at 140 K with an incident energy of 17 kcal/mole. The spectrum is shown in Fig. 4a. A low surface temperature is chosen in order to trap the nascent product of the dissociative chemisorption and not a thermal decomposition product. The temperature of the surface has no effect on the probability for dissociative chemisorption since the dissociation occurs immediately upon impact of the molecule on the surface. 

Electron energy-loss spectrum for biphenyl deposited on a thin film of solid argon at 20 K [106]. 

The inset in Fig. 3.30 shows a t)q)ical electron energy-loss spectrum of CePd2Si2 taken at a primary energy of the incident electron beam of Fp = 27 eV. Two characteristic features are present in the spectrum a pronounced peak at... 

Fig. 3.30 Electron energy-loss spectrum of CePd2Si2 taken at room temperature with a primary energy of the incident electron beam of = 27 eV the prominent feature at a loss energy of 1.2 eV is caused by a dipole-forbidden 4/- transition of the Ce eompound (see inset). The intensity of this feature is shown as a function of the electron excitation energy demonstrating a variation of the relative cross section. Reprinted with permission liom [49]. Copyright (1998) by the American Physical Society...

Summarizing thus, an electron energy loss spectrum may be characterized as follows If a monochromatic electron beam of primary energy Ep is incident on a... 

By application of valence shell electron energy loss spectroscopy, inner shell electron energy loss spectroscopy, magnetic circular dichroism spectroscopy, as well as photoelectron and electron transmission spectroscopy it can be deduced that the ji-electron system of borazine resembles that of benzene [8]. Table 4/13 presents the Rydberg term value matrix and Table 4/14 the energies and assignments from the electron energy loss spectrum (EELS) [8]. 

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