Emission spectra supported films

CO to a Pd(l 1 l)-like thick film and a Pd monolayer supported on Ta(110) [30,31], The spectrum for a thick palladium film is in very good agreement with that observed for adsorption of CO on a single-crystal Pd(lll) surface. The features at 11 and 8 eV correspond to emissions fi om the 4o and (In + 5o) levels of CO, respectively [30,31], In the photoemission spectrum for the Pd monolayer the 4o and (In + 5o) peaks of CO appear at higher binding energy than in the ectrum for the Pd(lll)-like film, and there is also an extra shake-up satellite ( s peak) around 13.6 eV. The spectrum for CO on the Pd monolayer matches the ectrum seen for CO on Cu(lll) [30,31], where the bonding interactions between the admolecule and metal substrate are much weaker than on Pd(l 11). 

We have examined the emission spectra of a variety of polysilylenes as thin films and solutions. The solution fluorescence ther-mochromism provides evidence to support the rotational isomeric state model used to interpret the absorption spectrum. The structured character and low yield of phosphorescence in the alkyl polysilylenes suggest that the triplet is the immediate precursor to photochemical scission. The change in character of both fluorescence and phosphorescence on progressing from phenyl to naphthyl in the aryl series indicates that the transitions in the naphthyl polymers are principally ir—it. ... 

In Fig. 2, the Raman spectrum of polypropylene is shown. In this example, a 17-in. working distance objective was attached to a filter fiber-optically coupled probe. The probe was supported above the film and the probe position was adjusted so that the film was approximately in focus. In this example, it should be noted that no modification to the polymer film line was required. In addition. Fig. 2 presents the spectrum of both postex-truded molten polymer and drawn crystallized polymer. The spectra recorded on-line agreed with the published literature for polypropylene with the exception of the band at 490 cm from the 532-nm laser [16]. The bands at 490 cm are related to a mercury emission line at 546.0 nm from the room lights. The observation of this line and the laser line can be used to provide on-the-fly calibration information because these lines arise from fundamental atomic emissions therefore their frequency is invariant to the Raman... 

If a material could be made extremely thin, for example, to the level of a single layer of molecules, this thin layer would transmit almost all of the infrared radiation, so that its infrared transmission spectrum could be measured. In fact, it is possible to measure a mid-infrared transmission spectrum from a thin soap film. It is usually practically difficult, however, to maintain such a thin film without it being supported by a substrate. For a thin film supported on a substrate, its infrared spectmm is often obtained by utilizing a reflection geometry. Two reflection methods are available for measuring infrared spectra from substrate-supported thin films, depending on the dielectric properties of the substrates used. External-reflection (ER) spectrometry, which is the subject of this chapter, is a technique for extracting useful information from thin films on dielectric (or nonmetallic) substrates, while reflection-absorption (RA) spectrometry, described in Chapter 10, is effective for thin films on metallic substrates [1]. In addition to these two reflection methods, attenuated total-reflection (ATR) spectrometry, described in Chapter 13 and emission spectroscopy, described in Chapter 15 may also be useful in some specific cases. 

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