RAIR—See Reflection-absorption

Studies to determine the nature of intermediate species have been made on a variety of transition metals, and especially on Pt, with emphasis on the Pt(lll) surface. Techniques such as TPD (temperature-programmed desorption), SIMS, NEXAFS (see Table VIII-1) and RAIRS (reflection absorption infrared spectroscopy) have been used, as well as all kinds of isotopic labeling (see Refs. 286 and 289). On Pt(III) the surface is covered with C2H3, ethylidyne, tightly bound to a three-fold hollow site, see Fig. XVIII-25, and Ref. 290. A current mechanism is that of the figure, in which ethylidyne acts as a kind of surface catalyst, allowing surface H atoms to add to a second, perhaps physically adsorbed layer of ethylene this is, in effect, a kind of Eley-Rideal mechanism. 

RAIRS reflection absorption infra red spectroscopy (see IRAS)... 

For information on the analysis of surfaces by IR radiation instead of electrons, a complimentary technique known as reflection absorption infrared spectroscopy (RAIRS), see (a) http //www.uksaf.org/tech/rairs.html (b)http //www.cem.msu.edu/ cem924sg/Topicll.pdf For example, the development of fibers/fabrics that will actively adsorb and surface deactivate chemical and biological warfare agents — of increasing importance as new modes of terrorist activity continue to emerge. For more information, see (a) http //web.mit.edu/isn/(Institute of Soldier Nanotechnologies at M.I.T.). (b) Richards, V. N. Vohs, J. K. Williams, G. L. Fahlman, B. D. J. Am. Ceram. Soc. 2005,88,1973. 

Infrared spectroscopy, including Fourier-transform infrared (FTIR) spectroscopy, is one of the oldest and most widely used analytical techniques in adhesion-related research. Transmission infrared spectroscopy has been used to identify compounds used in formulating adhesives and to follow curing reactions. Attenuated total reflection (ATR) (see Infrared spectroscopy attenuated total reflection) has been used to probe the surface composition of polymers that have been surface modified by an etching process or by deposition of a film. More recently, reflection-absorption infrared spectroscopy (see Infrared spectroscopy RAIR) has been used to characterize thin films on the surfaces of reflecting substrates. 

For information on the analysis of surfaces by IR radiation instead of electrons, a complimentary technique known as reflection absorption infrared spectroscopy (RAIRS), see (a) http //www.uksaf. orgAech/rairs.html (b) http //www.cem.msu.edu/ cem924sg/Topicll.pdf... 

Carbon monoxide on metals forms the best-studied adsorption system in vibrational spectroscopy. The strong dipole associated with the C-O bond makes this molecule a particularly easy one to study. Moreover, the C-0 stretch frequency is very informative about the direct environment of the molecule. The metal-carbon bond, however, falling at frequencies between 300 and 500 cm1, is more difficult to measure with infrared spectroscopy. First, its detection requires special optical parts made of Csl, but even with suitable equipment the peak may be invisible because of absorption by the catalyst support. In reflection experiments on single crystal surfaces the metal-carbon peak is difficult to obtain because of the low sensitivity of RAIRS at low frequencies [12,13], EELS, on the other hand, has no difficulty in detecting the metal-carbon bond, as we shall see later on. 

Recently, studies of monolayer film structure and composition have also been extended to nonmetal substrates, which have long been considered as unsuitable for RAIRS measurements due to their inherent low reflectivity and the often very complex band shapes of the film absorptions (see Figure 3B). In addition, the partial transparency of nonmetallic substrates also allows other surface techniques such as transmission or ATR spectroscopy to be used. The main advantages of RAIRS, on the other hand, are ... 

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