Infrared absorption and Raman scattering of (Z)-3-hydroxypropenal. A density functional theoretical study Original Research Article

The molecular and vibrational structure of (Z)-3-hydroxypropenal (β-hydroxyacrolein, malonaldehyde enol), a key compound in the study of intramolecular H-bonding, was investigated by a series of density functional theoretical (DFT) calculations. The vibrational frequencies obtained with the B3LYP, B3PW91, BLYP, or BPW91 density functionals are generally consistent with the spectral assignments recently suggested by S.F. Tayyari and F. Milani-Nejad [Spectrochim. Acta A 54 (1998) 255], but the DFT results are in much better quantitative agreement with the observed spectra than the MP2 results published by these authors, particularly in the case of B3LYP. Infrared and Raman vibrational transitions predicted with B3LYP/6-31G* and B3LYP/6-311++G** are reported for the title compound and some isotopomers, and the assignment of the infrared spectra of these compounds is discussed.