Phase transition studies in polar and nonpolar liquids at microwave frequencies

A resonant microwave cavity technique was employed to study the dielectric behavior of some polar and nonpolar liquids near the phase transition temperatures at microwave frequencies 7.2, 9.2 and 10.1 GHz. The Slater perturbation equations for a resonant microwave cavity are briefly discussed to show that the above technique can be used to determine both the real and imaginary parts of dielectric response. Abrupt changes in dielectric response were observed near the phase transition temperatures for the polar liquids studied.