Knowledge Bank

The microwave spectra of the $v=0$ to $v=4$ torsional states of glycolic acid have been assigned and the torsional energies determined from relative intensity measurements. The ground state spectra of $CH2ODCOOH$ and $CH2OHCOOD$ have also been assigned. Rotational constants for the normal species ground state are $10696.05\pm 0.04$, $4050.94\pm 0.01$, $2994.64\pm 0.01$ MHz. The torsional energies $(cm-1)$ are $109.9\pm 1.3$, $217.8\pm 3.3$, $323.4\pm 1.4$, and $426.8\pm 4.8$ for the $v=0$ to $v=4$ states, respectively, where the error limits are one standard deviation of the average.