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Raman spectra 418 INDEX

Some Properties of Xe(OSOtF)2.— Die Raman spectrum is compared with those of FXeOSOtF and StOoFt in Table III. Single crystals of Xe(OS02F)t were obtained by slow evaporation of a HF solution and fragmentary precession photograph data, from such a crystal, provided for the indexing of the X-ray powder data given in Table IV. The unit cell is monoclinic with a = 7.94, b = 13.7, c = 6.84 A, 0 = 96 . A small sample of Xe(OSOtF)2 under a dynamic vacuum at 20 slowly decomposed but none of the compound collected in the limbs of a U tube, cooled at —75°, provided to trap it. [Pg.208]

Both samples gave the same X-ray powder pattern which was indexed on the basis of a primitive rhombohedral unit cell (see Table III). The Raman spectrum is shown in Figure 1 (6) and is summarized in Table II. The solid can be stored indefinitely at dry ice temperature but is not stable at room temperature and liquifies and dissociates into its components within a few days. Although the dissociation pressure of the material was less than 5 Torr at 20°C it slowly volatilized under dynamic vacuum. [Pg.302]

This paper summarizes the results of our study of PE and APE waveguides in LiNb03 and EiTa03. We foeused on the optical and structural characterization of PE layers formed on Z-eut substrates. The reffaetive index ehange was measured and the propagation losses were estimated. Raman speetroseopy was used as a method providing direct information about the phonon spectrum. The latter was related to the structure and ehemieal bonds of a given erystalline phase. Sueh information may be useful for eorreet identification of both phase eomposition and the microscopic mechanisms responsible for the observed variation of the properties from phase to phase. [Pg.230]

Although optical resonance spectroscopy is suitable for studying chemical reactions involving two reactants and a single product, it cannot be extended to more than two or three components because one cannot interpret the resonance spectrum uniquely to obtain the composition from the refractive index. Raman spectroscopy is an attractive alternative approach. [Pg.84]

FI5. N. N. Greenwood, E. J. F. Ross, and B. P. Straughan, Index of Vibrational Spectra of Inorganic and Organometallic Compounds, Volume 1, 1935-1960. Butterworth, London, 1972. This publication arose as a result of literature surveys carried out for B6.1. Compounds are arranged by molecular formula, and for each, the physical state, type of spectrum (IR, Raman, etc.), and range are listed. [Pg.388]

With the ever-increasing need to improve quality and productivity in the analytical pharmaceutical laboratory, automation has become a key component. Automation for vibrational spectroscopy has been fairly limited. Although most software packages for vibrational spectrometers allow for the construction of macro routines for the grouping of repetitive software tasks, there is only a small number of automation routines in which sample introduction and subsequent spectral acquisition/data interpretation are available. For the routine analysis of alkali halide pellets, a number of commercially available sample wheels are used in which the wheel contains a selected number of pellets in specific locations. The wheel is then indexed to a sample disk, the IR spectrum obtained and archived, and then the wheel indexed to the next sample. This system requires that the pellets be manually pressed and placed into the wheel before automated spectral acquisition. A similar system is also available for automated liquid analysis in which samples in individual vials are pumped onto an ATR crystal and subsequently analyzed. Between samples, a cleaning solution is passed over the ATR crystal to reduce cross-contamination. Automated diffuse reflectance has also been introduced in which a tray of DR sample cups is indexed into the IR sample beam and subsequently scanned. In each of these cases, manual preparation of the sample is necessary (23). In the field of Raman spectroscopy, automation is being developed in conjunction with fiber-optic probes and accompanying... [Pg.540]

Figure 37. Observed intensity of the Raman line Ro, and the Compton line Ca of manganese versus incident photon energy the index a, indicates that the scattering process creates a final vacancy in the Ly subshell. Error bars associated with the Compton intensity account for the small observed fraction of the whole spectrum whose shape is not known. Lines through the points are to guide the eye only. (From Ref. 112.)... Figure 37. Observed intensity of the Raman line Ro, and the Compton line Ca of manganese versus incident photon energy the index a, indicates that the scattering process creates a final vacancy in the Ly subshell. Error bars associated with the Compton intensity account for the small observed fraction of the whole spectrum whose shape is not known. Lines through the points are to guide the eye only. (From Ref. 112.)...
These spectra were plotted from runs on a Jarrell-Ash 25-300 Raman spectrophotometer with a 4880 A argon ion laser. In some spectra the region from 4000 to 2000 cm" has been plotted so that the intensity is 0.5 times its true value compared to the rest of the spectrum. These are marked xO.5. Like the infrared spectra, these Raman spectra illustrate a group frequencies which are labeled directly on the spectra. Groups illustrated include alkanes in spectra 1-6, cyclohexanes 7-8, aromatics 9-12,15,17,18,20,21,25, 32-34, double bonds 13,14,24, isocyanate 15, triple bond 16, nitrile 17,18, carbonyls 19-26, alcohols 27-29, ether 30, amines 31, 32, nitro 33, C—Cl 34, C Br 35, and mercaptan 36. A molecular formula index of the Raman spectra follows. [Pg.478]


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