Temperature Dependence of 14N NQR and Phase Transitions in KNO2 Powder

Abstract

Abstract The temperature dependence of 14N NQR, measured at 77 to 300 K, is in better agreement with the model proposed by Blinc et al. than the Bayer theory. The nuclear quadrupole coupling constant and asymmetry parameter show a discontinuity at about 160 K and 230 K, respectively. The linewidths are broadened at these temperatures up to 22 kHz and 18 kHz, respectively. These results indicate that KNO2 undergoes phase transitions at these two temperatures.