NQR Study of the Structural Phase Transition in 1,2-Diphenylhydrazine

Abstract

¹⁴N NQR lines in 1,2-diphenylhydrazine have been investigated between 4.2 K and 370 K by using a pulsed spectrometer. With increasing temperature, the number of resonance line in NQR spectra decreased from six lines to three lines above 115 K. The temperature dependence of resonance lines reveals that 1,2-diphenylhydrazine makes a second order structural phase transition around 115 K. An information about the molecular structure is also obtained.