High-resolution electron-energy loss

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.]...

HREELS High-resolution electron energy-loss spectroscopy [129, 130] Same as EELS Identification of adsorbed species through their vibrational energy spectrum... 

As the table shows, a host of other teclmiques have contributed a dozen or fewer results each. It is seen that diffraction teclmiques have been very prominent in the field the major diffraction methods have been LEED, PD, SEXAFS, XSW, XRD, while others have contributed less, such as NEXAFS, RHEED, low-energy position diffraction (LEPD), high-resolution electron energy loss spectroscopy (HREELS), medium-energy electron diffraction (MEED), Auger electron diffraction (AED), SEELFS, TED and atom diffraction (AD). 

Analysis of Surface Molecular Composition. Information about the molecular composition of the surface or interface may also be of interest. A variety of methods for elucidating the nature of the molecules that exist on a surface or within an interface exist. Techniques based on vibrational spectroscopy of molecules are the most common and include the electron-based method of high resolution electron energy loss spectroscopy (hreels), and the optical methods of ftir and Raman spectroscopy. These tools are tremendously powerful methods of analysis because not only does a molecule possess vibrational modes which are signatures of that molecule, but the energies of molecular vibrations are extremely sensitive to the chemical environment in which a molecule is found. Thus, these methods direcdy provide information about the chemistry of the surface or interface through the vibrations of molecules contained on the surface or within the interface. 

High-Resolution Electron Energy Loss Spectroscopy (HREELS) 1.8.3... 

High-Resolution Electron Energy Loss Spectroscopy... 

Figure 2 Schematic of a 127° high-resolution electron energy-loss spectrometer mounted on an 8-in flange for studies of vibrations at surfaces.

In recent years there is a growing interest in the study of vibrational properties of both clean and adsorbate covered surfaces of metals. For several years two complementary experimental methods have been used to measure the dispersion relations of surface phonons on different crystal faces. These are the scattering of thermal helium beams" and the high-resolution electron-energy-loss-spectroscopy. ... 

Another spectroscopic technique, high-resolution electron energy loss spectroscopy (HREELS), has been used by Wagner and Moylan211 in combination with cyclic voltammetry to estimate ffs0of a Pt(lll) electrode from the reaction of H30+ formation. 

Hartree-Fock wave functions, 269 High resolution electron energy loss spectroscopy, HREELS, 43, 69 Highest occupied molecular orbital, HOMO, 269... 

HRELS = high-resolution, electron-energy-loss spectroscopy. " Surf. Sci. (in press). Ref. (123). Ref (101). Softened pCHj surface-mode. Weak band observed around 1500 cm could be a surface-dipole-forbidden, Pfc mode. Hidden under intense SCHj mode of free C2H4 in the matrix. " One of these bands belongs to Ni2(C2H4)2. 

The reactions of ethylene, water, and methanol with coadsorbed oxygen on Pdf 100) were studied with temperature programmed reaction spectroscopy (TPRS) and high resolution electron energy loss spectroscopy (EELS). 

HREELS high-resolution electron energy loss spectroscopy... 

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. 

Ammonia oxidation was a prototype system, but subsequently a number of other oxidation reactions were investigated by surface spectroscopies and high-resolution electron energy loss spectroscopy XPS and HREELS. In the case of ammonia oxidation at a Cu(110) surface, the reaction was studied under experimental conditions which simulated a catalytic reaction, albeit at low... 

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