Dielectric properties of Cs2BX4 (B=Zn, Co; X=Cl, Br, I)

Abstract Crystal growth was carried out by the Bridgman method for six substances of the Cs2 BX 4-type with β-K2SO4 structure, where B=Zn, Co and X=Cl, Br, I. The dielectric constants were measured to investigate their phase transitions. It has been shown that Cs2ZnI4 and Cs2CoI4 exhibit clear first order transitions at 93K and 51K, respectively, whereas the other four substances exhibit a broad dielectric anomaly at low temperatures.