Electron-stimulated

ESD Electron-stimulated (impact) desorption [148, 149] An electron beam (100-200) eV) ejects ions from a surface Surface sites and adsorbed species... 

ESDIAD Electron-stimulated desorption ion angular distribution [150-152] A LEED-like pattern of ejected ions is observed Orientation of adsorbed species... 

The nature of reaction products and also the orientation of adsorbed species can be studied by atomic beam methods such as electron-stimulated desorption (ESD) [49,30], photon-stimulated desoiption (PDS) [51], and ESD ion angular distribution ESDIAD [51-54]. (Note Fig. VIII-13). There are molecular beam scattering experiments such... 

An electron or photon incident on a surface can induce an electroiuc excitation. When the electroiuc excitation decays, an ion or neutral particle can be emitted from the surface as a result of the excitation. Such processes are known as desorption induced by electroiuc transitions (DIET) [82]. The specific teclmiques are known as electron-stimulated desorption (ESD) and photon-stimulated desorption (PSD), depending on the method of excitation. 

Ramsier R D and Yates J T Jr 1991 Electron-stimulated desorption principles and applications Surf. Sc/. Rep. 12 243... 

A number of surface-sensitive spectroscopies rely only in part on photons. On the one hand, there are teclmiques where the sample is excited by electromagnetic radiation but where other particles ejected from the sample are used for the characterization of the surface (photons in electrons, ions or neutral atoms or moieties out). These include photoelectron spectroscopies (both x-ray- and UV-based) [89, 9Q and 91], photon stimulated desorption [92], and others. At the other end, a number of methods are based on a particles-in/photons-out set-up. These include inverse photoemission and ion- and electron-stimulated fluorescence [93, M]- All tirese teclmiques are discussed elsewhere in tliis encyclopaedia. 

EID = electron impact desorption ESCA = electron spectroscopy for chemical analysis ESD = electron-stimulated desorption ... 

ESDIAD Electron-stimulated desorption ion angular distribution IPES Inverse photoemission spectroscopy... 

Electron Stimulated Desorption (ESD) and ESD Ion Angular Distribution (ESDIAD)... 

The most common ions observed as a result of electron-stimulated desorption are atomic (e. g., H, 0, E ), but molecular ions such as OH", CO", H20, and 02" can also be found in significant quantities after adsorption of H2O, CO, CO2, etc. Substrate metallic ions have never been observed, which means that ESD is not applicable to surface compositional analysis of solid materials. The most important application of ESD in the angularly resolved form ESDIAD is in determining the structure and mode of adsorption of adsorbed species. This is because the ejection of positive ions in ESD is not isotropic. Instead the ions are desorbed along specific directions only, characterized by the orientation of the molecular bonds that are broken by electron excitation. 

An Auger Electron Spectroscopic and Electron-Stimulated Desorption Study... 

Fig. 10 EPR spectra of TF" centers at 40 K after electron stimulated TiCU deposition and subsequent electron bombardment. Top defective MgCb film bottom defect-free MgCb film...

Toci, F. Modica, G., Hydrogen production by in-situ cracking of steam-bioethanol mixtures combining electronic stimulation with chemical catalysts. In 9th European Bioenergy Conference, Chartier, Ph. Ferrero, G. L. Henius, U. M. Hultberg, S. Sachau, J. Wiinblad, M. Eds., Copenhagen, 1996, p. 425. 

In HRTEM, very thin samples can be treated as weak-phase objects (WPOs) whereby the image intensity can be correlated with the projected electrostatic potential of crystals, leading to atomic structural information. Furthermore, the detection of electron-stimulated XRE in the electron microscope (energy dispersive X-ray spectroscopy, or EDX, discussed in the following sections) permits simultaneous determination of chemical compositions of catalysts to the sub-nanometer level. Both the surface and bulk structures of catalysts can be investigated. 

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