The particle-size dependence of the dielectric behaviour of SbSI

Abstract
The results of dielectric constant measurements for different particle-sized samples of SbSI from 64 to 420 mu m are reported in the frequency range 1-100 kHz and temperature range from -20 to 50 degrees C. The dielectric anomaly indicating ferroelectric-paraelectric transition has been observed at 19 degrees C for the particles greater than 150 mu m. Below 150 mu m the dielectric anomaly completely disappears. The dielectric constant is found to decrease with decreasing particle size and a dielectric dispersion is observed in the frequency range 1-100 kHz. These results have been explained by proposing a defective surface layer model of lower dielectric constant than the bulk.