Acetic acid vibrational assignments

Table 3-XVI presents some of the assignments for these modes in the monomeric and dimeric states. The relative shifts are uniformly high, near 0.1, with the notable exception of that of deuteroformic acid. This deviation cannot be discounted, because the assignments of formic acid are among the least ambiguous. Nevertheless, we can generalize that most workers propose that two vibrations of carboxylic acids involve Vb and that both of these vibrations move upward in frequency up>on H bond formation. The magnitudes of Lvb/Vb suggest that Vb may be almost as sensitive to the H bond perturbation as v, Av,/v, for acetic acid is about 0.14, 979). It must be remembered, of course, that...

Table 3. Solvation effects on calculated frequencies (scaled by 0.893) of acetic acid and acetate compared to experimental values in aqueous solution (Kubicki et al. 1999c). (Note Band assignments based on calculated vibrational modes in these model clusters, not experimental data.)...

It has been demonstrated using lETS [28] that when the ester-containing polymers polymethyl methacrylate and polyvinyl acetate are placed in contact with aluminium oxide, peaks which can be assigned to the carboxylate ion arise. Specifically, these are due to the symmetric and asymmetric vibrational modes of -COO which are located at about 1450 and 1610 cm F More recently, Devdas and Mallik [29] showed, using lETS, that a number of carboxylic acids adsorbed on alumina show such peaks an example is that pyruvic acid CH3CH2COCOOH shows the peaks at 1450 and 1605 cm . 

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