Optical techniques electron energy loss spectroscopy

The first two advantages listed above allow an optical method like transmission or reflection IR spectroscopy to be used for studies which would be impossible for a widely used competitive technique, electron energy loss spectroscopy (EELS). EELS must... 

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. 

These experiments further illustrate that electron energy loss spectroscopy with cFEG TEM is a powerful method to study the electronic structure of solids. The drawback of this technique is the poor energy resolution compared with that of the optical techniques. With the advance of spectroscopy technol-... 

Probing plasmonic resonances using low-loss electron energy loss spectroscopy has proved particularly useful for studying the optical properties of noble metal nanoparticles. Single particle plasmonic studies are an important tool to understand the role of size, shape and local environment on the exact nature of plasmonic excitations that might be complicated by dispersity of these traits when using bulk techniques. 

Chemical reactions at the gas-surface interface can be followed by monitoring gas-phase products with, for example, a mass spectrometer, or by directly analyzing the surface with a spectroscopic technique such as Auger electron spectroscopy (AES), photoelectron spectroscopy (PES), or electron energy loss spectroscopy (EELS), all of which involve energy analysis of electrons, or by secondary ionization mass spectrometry (SIMS), which examines the masses of ions ejected by ion bombardment. Another widely used surface probe is low-energy electron diffraction (LEED), which can provide structural information via electron diffraction patterns. At the gas-liquid interface, optical reflection elHpsometry and optical spectroscopies are employed, such as Eourier transform infrared (ET IK) and laser Raman spectroscopies. 

In the fields of solid-state and molecular physics, there have been many different experimental techniques introduced for vibrational spectroscopy. However, the investigation of the vibrational properties of bare solid surfaces is dominated by the two techniques of helium atom scattering (HAS) and high-resolution electron energy loss spectroscopy (HREELS). Both have been used to map surface phonon dispersions. In addition, that is, optical techniques such as infrared absorption spectroscopy (IRAS) (Chapter 3.4.1) and recentiy also inelastic tunneling... 

Apart from the theoretical approaches, electronic energy spectra of carbides and nitrides have been studied using a variety of experimental techniques X-ray emission and photoelectron spectrosopy, optical and Auger spectroscopy, electron energy loss and positron annihilation spectroscopy, etc. However, interpretation of the results obtained requires, as a rule, use of the computational methods of the band theory of solids and quantum chemistry. Moreover, the data provided by theoretical methods are important by themselves, because they give much more detailed information on the electron states and chemical bonding than any of the experimental methods. They also allow us to model theoretically... 

Breysse, M., B. Claudel, L. Faure and M. Guenin, 1978, Chemiluminescence induced by Catalysis, in The Rare Earths in Modem Science and Technology, eds. GJ. McCarthy and J.J. Rhyne (Plenum, New York) p. 99. Brousseau, B., F. Frandon, C. Colliex, P. Trebbia and M. Gasgnier, 1974, Energy Loss Spectra and Optical Constants of Rare Earth Metals, Hydrides and Oxides between 5 and 200 eV, in Vacuum UV Radiation Physics, eds. E. Koch, R. Haensel and C. Kunz (Per-gamon-Vieweg, Braunschweig) p. 622. Brundle, C.R. and A.D. Baker eds., 1978, Electron Spectroscopy Theory, Techniques and Applications, Vol. 2 (Academic Press, London). 

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