Stretching vibration compounds

Mercaptans and thiophenols absorb at 2590-2540 cm due to the SH stretching vibration. Compounds with a BH group absorb at 2630-2350 cm . Compounds with a PH group absorb at 2440-2275 cm. Compounds with an SiH group absorb at 2250-2100 cm ... 

The C=0 stretching vibrations of these compounds may be viewed on Learning By Modeling... 

The Raman spectrum of aqueous mer-cury(I) nitrate has, in addition to lines characteristic of the N03 ion, a strong absorption at 171.7 cm which is not found in the spectra of other metal nitrates and is not active in the infrared it is therefore diagnostic of the Hg-Hg stretching vibration since homonuclear diatomic vibrations are Raman active not infrared active. Similar data have subsequently been produced for a number of other compounds in the solid state and in solution. 

Gas-phase studies where relevant tautomeric compounds are described are ihore scarce, but include uracil, thymine, and adenine [97CPL(269)39]. In the case of the 2-pyridone/hydroxypyridine equilibrium, the intensity of the OH and NH stretching vibrations was measured for eight temperatures in the range from 428 to 533 K in the gas phase. This allows determination otAH and AS for the equilibrium (92JPC1562). 

The 13C-NMR spectra of 4-7, 9-11 show a close similarity to the spectral data of analogous carbene complexes. The shift differences between the metal carbonyls of the silylene complexes and the related carbon compounds are only small. These results underline the close analogy between the silicon compounds 4-7, 9-11 and Fischer carbene complexes. This view is also supported by the IR spectral data. On the basis of an analysis of the force constants of the vco stretching vibration,... 

Much earlier information on the structure of diazonium ions than that derived from X-ray analyses (but still useful today) was obtained by infrared spectroscopy. The pioneers in the application of this technique to diazonium and diazo compounds were Le Fevre and his school, who provided the first IR evidence for the triple bonds by identifying the characteristic stretching vibration band at 2260 cm-1 (Aroney et al., 1955 see also Whetsel et al., 1956). Its frequency lies between the Raman frequency of dinitrogen (2330 cm-1, Schrotter, 1970) and the stretching vibration frequency of the C = N group in benzonitrile (2255 cm-1, Aroney et al., 1955). In substituted benzenediazonium salts the frequency of the NN stretching vibration follows Hammett op relationships. Electron donor substituents reduce the frequency, whereas acceptor substituents increase it. The 4-dimethylamino group, for example, shifts it by 103 cm-1 to 2177 cm-1 (Nuttall et al., 1961). This result supports the hypothesis that... 

The absorption at 1600 cm-1 in the plutonium compounds is slightly lower than that expected for a C=C stretching vibration. ( 5) The C-C vibration in C2HltI2 is found at 1128 cm-1, and coordination or bonding of a C H I moiety would be expected to lower this value.(6) However, coordination or bonding of a C=C linkage would be expected to both lower the frequency and increase the intensity... 

Infrared Intensities of Metal Carbonyl Stretching Vibrations, 10, 199 Infrared and Raman Studies of w-Complexes, 1, 239 Insertion Reactions of Compounds of Metals and Metalloids, 5, 225 Insertion Reactions of Transition Metal-Carbon o-Bonded Compounds I Carbon Monoxide Insertion, 11, 88... 

Two other publications on Ir (73 keV) Mossbauer spectroscopy of complex compounds of iridium have been reported by Williams et al. [291,292]. In their first article [291], they have shown that the additive model suggested by Bancroft [293] does not account satisfactorily for the partial isomer shift and partial quadrupole splitting in Ir(lll) complexes. Their second article [292] deals with four-coordinate formally lr(l) complexes. They observed, like other authors on similar low-valent iridium compounds [284], only small differences in the isomer shifts, which they attributed to the interaction between the metal-ligand bonds leading to compensation effects. Their interpretation is supported by changes in the NMR data of the phosphine ligands and in the frequency of the carbonyl stretching vibration. 

The only doubly bonded tin compound for which the IR spectrum has been reported is the stannaketenimine [2,4,6-(CF3)3C6H2]2Sn= C=N[2,4,6-(CH3)3C6H2)]. The C—N stretching vibration (2166 cm-1) is shifted relative to that of mesityl isocyanide (2118 cm-1) this phenomenon is also observed for isocyanide-transition-metal complexes.87... 

A shift of stretching vibrations vc=0 from 1590 to 1640 cm-1 is observed in the mixture of model compounds which points to intermolecular coordination interactions. 

The electronic spectra of [Ir2(tmb)4L2]2+ binuclear compounds (L = C1, Br, I) have intense dander transitions between 37,000cm-1 and 30,000cm-1.486 Irn-Irn stretching vibrations are observed between 140 cm-1 and 116 cm-1, from which Ir2 force constants are evaluated. 

A large number of calculations have been done to determine the vibrational frequencies of some simple silenes. The parent silene and its deuterated analogs have been investigated (4,9,188) as well as 1,1-dimethylsilene, its deuterated derivatives (38,181), and 1,1-dichlorosilene (4). For the undeuterated compounds a Si=C stretching vibration of approximately 1000 cm-1 was calculated. Deuteration usually results in a decrease of this value. 

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