Knowledge Bank

The vibrational spectra of iodoacetic acid have been studied in the liquid and solid states. Spectra of sodium iodoacetate and iodoacetic acid-$d1$ have been determined to aid in the assignment of the fundamental vibrations of the parent acid. In contrast to chloroacetic acid, the most stable polymorph of crystalline iodoacetic acid possesses the hydrogen bonded dimer structure. This structure appears to be maintained in the liquid phase. Only one rotational isomer is detectable in the liquid state.