Search for New Ferroelectrics in Tl 2 ZnI 4 Group

Our work of new ferroelecric survey was reviewed. A 2 BX 4 -type compounds having Sr 2 GeS 4 structure, where A = K, Rb, Tl and Cs, B = Zn, Co, Cd and Hg, X = I and Br, were synthesized by the Bridgman method. Their dielectric and phase transitional properties were investigated. From the results, several empirical relations among phase transition points and including elements were pointed out.