Raman measurements, carbonyl vibrations

Raman Measurements of the Carbonyl Vibrations Show No Evidence for Bifurcated Hydrogen Bonds. 

A theoretical determination of vibrational absorption and Raman spectra of 3-methylindole radicals has been carried out in comparison to experimentally measured spectra for 3-methylindole (Table 28) to provide specific spectroscopic markers for the detection of neutral or cationic tryptophan radicals in biological systems <2001CPH(265)13>. Among isatin derivatives, substitution at C-5 has relatively greater influence on the electron density and the force constant of the amide than of the ketone carbonyl group (Table 29) <2001SAA469>. 

The other vibrational spectroscopies, although less easily applied, may provide complementary structural information. Raman spectroscopy has been used to detect metal-metal bonds in metal oxide supported osmium [86] and iridium [87] clusters. This method might be expected to find application in the study of zeolite supported metal carbonyl dusters, but it is still far from routine since samples are subject to destruction by laser beams, and fluorescence often prevents measurement of useful spectra. 

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