The transition frequencies were taken from
(1) K. M. Marstokk and H. Møllendal, 1973, J. Mol. Struct., 15, 137;
and from
(2) B. Bakri, J. Demaison, L. Margulés, and H. Møllendal, 2001, J. Mol. Spectrosc., 208, 92.
This is the lowest energy conformer, which exhibits a hydrogen bond from the hydroxyl H atom to the O atom of the aldehydic carbonyl group.
5 lines from (1) fitting poorly were omitted from the line list.
Note: the small b-dipole moment component is very uncertain.
Predictions with uncertainties larger than 1 MHz should be viewed with caution.
The dipole moment components were determined in (1).