The reorientational motion of substituted benzenes in the crystalline state: phase transition and dielectric relaxation of nitropentachlorobenzene and tetrachlorometaxylene

Dielectric relaxation measurements have been performed on nitropentachlorobenzene and tetrachlorometaxylene in the frequency range 100 Hz to 1 MHz and in the temperature range 152–400 K. In addition, scanning calorimetric measurements have been carried out. From the results obtained, a possible mechanism has been suggested as regards the dielectric relaxation process.