Orientational order parameter and mean square displacement of solid heavy nitrogen in the low-temperature phase. Experimental data

This work presents the results of the analysis of the temperature dependence of the x-ray reflection intensity from solid heavy nitrogen in the ordered phase. The temperature dependence of the behavior of the orientational order parameter and mean square displacement of 15N2 molecules obtained from x-ray data is plotted. Based on the dependencies obtained, the orientational order parameter was determined at 0 K, which is 12% higher than the orientational order parameter obtained in theoretical works. It was found that the heavy nitrogen molecule “freely” rotates in the crystal at temperatures above 45 K.