Features in the dielectric properties and temperature-composition phase diagrams of NaNbO3-A(0.5)Bi(0.5)TiO(3) (A = Li, Na, K, Ag) solid solutions

In the systems of solid solutions (1 - x)NaNbO3 - xA(0.5)Bi(0.5)TiO(3) , wh ere A is Li (I), Na(II), K(III), and Ag(IV), the concentration dependence o f the temperature T-m, corresponding to a maximum in the dielectric permitt ivity epsilon, is described by a curve with minimum. In systems II and IV, a "break" is observed on the T-m(x) dependences in the region of x approxim ate to 0.2, and the compositions with x < 0.2 are characterized by anomalou sly large temperature hysteresis of epsilon(T) reaching 80-100 K. Some comp ositions of systems I and III have very diffuse peaks of epsilon(T) in the room temperature range, which is of interest from the standpoint of search for lead-free relaxer materials. (C) 2000 MAIK "Nauka/Interperiodica".