Raman data

KnowItAll Bio-Rad s SadtlerT software database solutions for spectroscopy numeric IR, NMR, MS, NIR, and Raman data Bio-Rad Laboratories, Inc. commercial CD-ROM periodi- cally www.bio-rad.- com... 

Vibrational spectra including Raman data of 3,3-dimethyldiaziridine and its hexadeutero compound were recorded in the gas phase and in the crystalline state. Assuming C2 symmetry and employing isotopic shifts and comparison with azetidine, a classification of bands which regarded 33 normal modes could be given (75SA(A)1509). 

Older Raman data obtained using a mercury lamp are available for the sul-fanes H2S (n=5-8) and for crude sulfane oil. However, there is some suspicion that the lines observed near 150 and 217 cm result from Ss as a byproduct of the preparation reactions or as a photochemical decomposition... 

Table III. Raman Data For Bl2FeMo20j 2 From Microreactor...

On the basis of infrared and Raman data 102), the structure is believed to have bridging halogen atoms between the metal atoms, the coordination geometry around each... 

These results confirm Resonance Raman studies of oxidized rubredoxin from Desulfovibrio gigas, which indicates that there are three bands (43.15, 45.01, and 46.62 meV 348, 363, and 376 cm ) in the region where asymmetric Fe° -S stretch modes are expected [108]. Resonance Raman data of the reduced rubredoxin... 

The structure of S7 is clearly the most intriguing59 61 of all known structures of neutral sulfur homocycles. Several modifications are known (sometimes only by powder or Raman data) however, the structural features are always the same and show a large bond length alternation and a range of S-S distances from 199 pm (bond order > > 1.0) to 218 pm (bond order < < 1.0 Figure 13). Other isomers were assessed by quantum chemistry.61... 

Figure 5. Absorption spectra and Raman data for 3 BCMU yellow and blue solutions. The data points indicate the co, dependence of vc=c. The conjugation length scale is an estimate of the length of a chromophore with absorption frequency co. (Reproduced with permission from Ref 21. Copyright 1982, American Institute of Physics.)...

The differences between the IR and Raman data under stress are not subtle. For the [100] stress direction, for example, there is no splitting observed in the IR spectrum (Fig. 17) the 1903 cm-1 band shifts to higher frequency without broadening for increasing stress up to 370 MPa. The... 

Raman data, however, show a clear splitting under [100] stress (Fig. 18 and 19) and with the larger of the split components shifting to lower frequency for increasing stress up to 16 kbar (1600 MPa). 

Correa, S. M. and S. B. Pope (1992). Comparison of a Monte Carlo PDF/finite-volume mean flow model with bluff-body Raman data. In Twenty-fourth Symposium (International) on Combustion, pp. 279-285. Pittsburgh, PA The Combustion Institute. 

The period under review has seen a small, but apparently real, decrease in the annual number of publications in the field of the vibrational spectroscopy of transition metal carbonyls. Perhaps more important, and not unrelated, has been the change in perspective of the subject over the last few years. Although it continues to be widely used, the emphasis has moved from the simple method of v(CO) vibrational analysis first proposed by Cotton and Kraihanzel2 which itself is derived from an earlier model4 to more accurate analyses. One of the attractions of the Cotton-Kraihanzel model is its economy of parameters, making it appropriate if under-determination is to be avoided. Two developments have changed this situation. Firstly, the widespread availability of Raman facilities has made observable frequencies which previously were either only indirectly or uncertainly available. Not unfrequently, however, these additional Raman data have been obtained from studies on crystalline samples, a procedure which, in view of the additional spectral features which can occur with crystalline solids (vide infra), must be regarded as questionable. The second source of new information has been studies on isotopically-labelled species. 

Experimentally, several precautions must be taken if reliable Raman data are to be obtained from solution studies. Firstly, the instrumental slit-width should be appreciably smaller than the half-width of the band to be studied. This means that slits wider than 2 cm-1 are to be avoided. Secondly, photolytic decomposition of the sample and local boiling of the solvent have also to be avoided. Careful choice of laser frequencies, use of a low incident power and, if necessary, sample spinning are indicated. The need for a relatively high solute concentration usually means that there is little choice of solvent. Particularly for coloured samples the presence of a vestigal resonance Raman effect must be tested by measurements with a variety of... 

Raman data (including intensities) and their interpretation for the low frequency region of LM(CO)s, L = Sn,Ge ligand, M = Mn,Re... 

Solution and crystalline infrared and Raman data for NiL(CO)3, L = PPh3, AsPh3 and their assignment... 

The IR spectra of M2(CO)jo M = Mn,Re,Tc with particular emphasis on 13CO-containing species. A comparative vibrational analysis is given (including Raman data)... 

The similarity of the UV and Raman data for these forms suggests that the disordered phases may comprise chains with essentially deviant backbone dihedral angles, even if the chains are not regularly aligned. 

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