Theoretical calculations of vibrational frequencies and derived potential energy distributions from normal coordinate analyses for 2,3-butadienal

The vibrational frequencies were computed at HF/6-31G** level for the cis and trans conformers of 2,3-butadienal. Normal coordinate calculations were carried out and potential energy distributions among symmetry coordinates were calculated for the two stable conformers of the molecule. The computed vibrational frequencies were scaled and compared to those observed experimentally for similar molecules.