Dielectric response of material media using the detuning of a resonant microwave cavity

The dielectric response of select fluids as they change phase from solid to liquid is studied. The experimental apparatus used to make the investigation is discussed in detail, pertaining to resonant frequency and cavity bandpass measurements for the loaded cavity. Results are presented for water ice, benzene, toluene, carbon disulfide, and 4-cyano-4-n-alkylbiphenyls as the temperature is cycled. For each of the samples studied, the cavity absorption profile was monitored for width at half-power, center resonant frequency, and absorption signal amplitude. These quantities are related to the dielectric properties of the materials loading the cavity.