Gel growth and dielectric studies of K, Rb and Cs perchlorates

Abstract

Single crystals of K, Rb and Cs perchlorates have been grown by the counter diffusion of the respective ions and ClO₄^– through the gel medium. Studies on nucleation, growth kinetics, morphological aspects and purity are discussed in this paper. The dielectric constant, ε_b, as well as loss measured along the longest axis, exhibits an anomaly at the transition temperature, T_t, in all the three crystals. It is found that the peak values of T_t are approximately 800, 100 and 53 in K, Rb and Cs perchlorates, respectively. The dielectric anomaly and the large value of ε_b in the cubic phase are discussed in terms of the degree of disorder of the ClO₄^– group and the possible contribution from defects.