Abstract
Binary NaNbO3-ABO3 perovskite solid solutions belonging to the group II according to N.N. Krainik classification (Izv. Akad. Nauk SSSR, Ser. Phys. 28, 643 (1964)) exhibit a relaxor-type behavior when the second component concentration exceeds a threshold value x0, corresponding to the abrupt decrease of the dielectric permittivity ϵ maximum temperature Tm. The Tm values of all the known binary NaNbO3-ABO3 relaxor compositions are well below the room temperature and the maximal ϵ values ϵm are much lower than in the case of Pb-containing relaxors. However both Tm and ϵm values may be increased substantially by Li or K-doping leading to the formation of ternary NaNbO3-ABO3-LiNbO3 (KNbO3) solid solutions.