Dipole-dipole interactions in potassium chloride doped with hydroxyl

The dielectric constant ε=ε^'-iε^'' of KCl doped with OH^- or OD^- has been measured within the temperature range 0.1-250 K, the frequency range 10²-10⁵ Hz, and the concentration range 0-4000 at. ppm. Discrete features appear in both ε^' and ε^'' which are related to a thermally activated, two-step reorientation of OH^- pairs. No evidence is found for a phase transition.