Thermophysical Behaviour of Crystalline Halides with Temperature

Abstract

The thermal conductivity, thermal diffusivity and volumetric heat capacity of monocrystalline AgCl and AgBr were measured simultaneously, by Advantageous Transient Plane Source method in the temperature range 77-350 K. Both thermal conductivity and thermal diffusivity follow Eucken’s law in the temperature region studied. The heat capacity at constant pressure (CP) determined from the volumetric heat capacity agrees with the calculated one at room temperature. The values of CP obtained from this experiment along with the reported data as a function of temperature are also reported. The ratio of the thermal conductivity (λ) of AgBr and AgCl calculated from the Leibfried-Schlömann (LS) formula are in excellent agreement with the ratio measured experimentally. The dielectric constant and loss factor, of these crystalline hallides, are also reported as a function of frequency in the range 100 Hz to 1 MHz at room temperature.