Temperature Dependence of the III—II Transition Rate of KNO3 at Atmospheric Pressure

The existence of ferroelectric behavior in the Phase III polymorph of potassium nitrate has permitted the direct recording of the rate of transition of the Phase III to the Phase II at temperatures far removed from the normal transformation temperature at atmospheric pressure. The data presented indicates that the III—II transition may be described by two first-order processes which may each be described by a single rate constant. These rate constants as a function of temperature are given.