Spectroscopic studies electron energy loss

Carbon monoxide chemisorption on Ni 7 9 11 represents an interesting case with which to check these concepts since comparable studies have been performed on Ni 001 and Ni lll and since a number of other experimental methods have been applied to this system. Electron energy loss spectroscopic (EELS) studies performed at 150 K suggest that the initial adsorption occurs in threefold and twofold bridge sites along the step edge. Beyond this point, the CO molecules begin to occupy terrace sites. (12)... 

Carbonization is one of the most drastic phenomena of electronic excitation effects induced by ion beams [1, 2]. The mechanisms of carbonization and the chemical structure of the carbon-rich layer are still controversial problems. Many spectroscopic techniques have been applied to studies of carbonization such as RBS [14], Raman [14], IR [15], ESR [16], ESCA [17], electron microscope [18, 19] and electron energy loss spectroscopy in normal and reflection mode [20]. 

There is a number of vibrational spectroscopic techniques not directly applicable to the study of real catalysts but which are used with model surfaces, such as single crystals. These include reflection-absorption infrared spectroscopy (RAIRS or IRAS) high-resolution electron energy loss spectroscopy (HREELS, EELS) infrared ellipsometric spectroscopy. 

Future studies should emphasize the further application of spectroscopic techniques, AES, LEED, electron energy loss spectroscopy (EELS), and laser Raman spectroscopy to provide a more quantitative understanding of the interaction of sulfur compounds with metal surfaces. 

The structure and reactivity of ethylene chemisorbed on transition-metal surfaces are of fimdamental importance in surface science and heterogeneous catalysis. HREELS has been foremost among the surface characterization techniques employed in fact, the first vibrational spectroscopic study of ethylene chemisorbed on Pt(lll) was carried out with electron energy-loss spectroscopy (EELS) almost a decade before IRAS was employed. ... 

The electronic structure of corundum type oxide surfaces have been studied with photoelectron spectroscopy [102, 103] as well as with electron energy loss spectroscopy [104]. Henderson and Chambers [103] have reeently reviewed the photoelectron spectroscopic evidences. Still, there seems to be an ambiguity about the oxidation state of the chromium ions in the immediate surface layer. XPS Cr 2p data may be to a large extent reconciled as being due to Cr(III) in the surface, because there is obviously no change in the spectra as a function of... 

Vibrational spectroscopy is an important probe used to determine the bonding and structural properties of molecules. Powerful techniques such as electron energy loss spectroscopy (EELS) have been developed, which allow one to obtain the vibrational properties of molecules chemisorbed upon surfaces. Due to low concentration, the highly reactive nature of the clusters, and the large number of possible species which are typically present in the cluster beams used to date, unconventional techniques are required in order to obtain spectroscopic information. One unconventional but powerful technique, infrared multiple photon dissociation (IRMPD), has recently been applied to the study of the vibrational properties of gas-phase metal clusters upon which one or more molecules have been chemisorbed. This same technique, IRMPD, has previously been used to obtain the vibrational spectra of ions, species for which it is difficult to apply conventional absorption techniques. 

Structural Studies. In a number of communications,22-26 correlations have been sought between both the spectroscopic and chemical properties of the various carbon allotropes and their structures. Thus, an electron-energy-loss spectroscopic study22 of diamond, graphite, and amorphous carbon has shown that the differences in the X-shell ionization loss spectra of the three allotropes (Figure 1) might be the basis of a technique for distinguishing... 

The experimental detection and quantification of surface species on in situ soil particles and other natural colloids is a difficult area of research because of the sample heterogeneity, low surface concentrations, and the necessity to investigate the solid adsorbents in the presence of water. Unambiguous information can be obtamed only with in situ surface spectroscopy, such as x-ray photoelectron (XPS), extended x-ray absorption hne structure (EXFAS), x-ray absorption near-edge structure (XANES), melastic electron tunneling (lETS), and electron energy loss (EELS) spectroscopies. Recent advances in the development of nonevasive, in situ spectroscopic scarmed-probe and microscopic techniques have been applied successfully to study mineral particles in aqueous suspensions (Hawthorne, 1988 Hochella and White, 1990). 

From examining the spectroscopic characteristics of diamond films, many insights into their structure may be obtained. Most of all the Raman spectroscopy, XRD and electron energy loss spectroscopy (EELS) provide valuable information. Other methods like IR-spectroscopy and XPS shed light on the surface structure. These techniques are supplemented by microscopy methods, for example, by AFM and STM, so altogether the morphology of the films surface can be studied in quite some detail. 

Smith , DeWitt JG, Hedman B, Hodgson (1994) Sulfur and chlorine -edge X-ray absorption spectroscopic studies of photographic materials. J Am Chem Soc 116 3836-3847 Sodhi RNS, Brion CE (1985a) High resolution carbon Is and valence shell electronic excitation spectra of trans-1,3-butadiene and allene studied by electron energy loss spectroscopy. J Electron Spec Rel Phen 37 1-21... 

V.H. Grassian and E.L. Muetterties. Vibrational Electron Energy Loss Spectroscopic Study of Benzene, Toluene, and Pyridine Adsorbed on Pd(lll) at 180 K. J. Chern. Phys. 91 389 (1987). 

Gorodetskii, V.V. and Drachsel, W., Kinetic oscillations and surface waves in catalytic CO - - O2 reaction on Pt surface field electron microscope, field ion microscope and high resolution electron energy loss spectroscope studies, Appl. Catal. A Gen., 188, 267-275, 1999. 

Electron energy loss-spectroscopic studies illustrated accumulation of the central metal atoms titanium and vanadium in those cellular regions which are rich in nucleic adds. 

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