The Effect of a Foreign Substance on the Transition: Nh4no3ivnh4no3 Iii

It is shown that the above transition can be repressed (metastably) by using in place of pure ammonium nitrate a solid solution of potassium nitrate in ammonium nitrate. With such a solid solution containing 8 to 10% potassium nitrate, the temperature of the transition III → IV is depressed to about −20 °C. Such solid solutions can be prepared either by fusing the components together or by crystallizing from a mixed aqueous solution.