Raman spectra stretching region

A Raman spectrum of p-S is shown in Fig. 29. While the Raman lines in the stretching region (430-520 cm ) are of high intensity, exceeding those... 

Given the nature of the Raman spectrum in the OH stretching region, and the fact that the spectral decomposition used is not unique, any set of assignments for the several components must be considered tentative. The following, based on a "common sense analysis, seems reasonable ... 

The low frequency Raman spectrum of the 6-coordinate models is distinctly different from the low frequency spectrum of the 5-coordinate sites of the Ni gjobins. In fact only one line, a very weak shoulder on the 300-cm line, is obserYed in the expected metal-ligand stretching region below 300 cm. Further no predominately Ni stretches are found in the 100-500-cm region. Instead, in both the 6- and 5-coordinate c mp xes many of the low frequency Raman lines show small (< 1 cm ) Ni isotopic shifts indicating some pyppole... 

Figure 2.7 Vibrational excitation spectra in the region of the fundamental N-H and C-H symmetric stretches of pyrrole (a) photoacoustic Raman spectrum in a static cell at a pressure of 6.5 Torr and (b) H action spectrum obtained by 243.135 nm dissociation of jet-cooled molecules at a delay of 10 ns between the SRS and UV beams. The intensity scale of each panel is different. Reproduced with permission from Ref. [87]. Copyright (2011) AlP Publishing LLC.

The N=N stretching vibration of a symmetrical trans-azo compound is forbidden in the IR but absorbs in the 1576 cm-1 region of the Raman spectrum. Unsymmet-rical para-substituted azobenzenes in which the substituent is an electron-donating group absorb near 1429 cm1. The bands are weak because of the nonpolar nature of the bond. 

The possibility of obtaining information about lipid-protein interaction makes Raman spectroscopy a useful technique for structural studies of membranes. As an illustration of spectra recorded from biological samples, see the Raman spectrum of a frog sciatic nerve in Figure 11. The C-H stretching vibration region is characteristic of lipid bilayers in a... 

The infra-red spectrum of Mo(CO)3[P(OCH3)3]3 (VIII) shows three absorption bands at 1993,1919, and 1890 cm-1 in the region in which CO stretching frequencies usually appear. But Cr(CO)3(CNCH)3 (IX) has two absorption bands in the C—O stretch region at 1942 and 1860 cm-1. Octahedral ML3(CO)3 complexes can exist in either the mer or fac isomeric forms (Figure 9.2). Assign the structures of the above two molecules. How many bands would you expect to see in the vibrational Raman spectra of these two molecules, and for which of these bands would the scattered Raman radiation be polarized ... 

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