Title: Relative stability of a ferroelectric state in (Na0.5Bi0.5)TiO3-based compounds under substitutions: Role of a tolerance factor in expansion of the temperature interval of stable ferroelectric state,
Abstract: The influence of the B-site ion substitutions in
(1-x)(Bi1/2Na1/2)TiO3-xBaTiO3 system of solid solutions on the relative
stability of the ferroelectric and antiferroelectric phases has been studied.
The ions of zirconium, tin, along with (In0.5Nb0.5), (Fe0.5Nb0.5), (Al0.5V0.5)
ion complexes have been used as substituting elements. An increase in the
concentration of the substituting ion results in a near linear variation in the
size of the crystal lattice cell. Along with the cell size variation a change
in the relative stability of the ferroelectric and antiferroelectric phases
takes place according to the changes of the tolerance factor of the solid
solution. An increase in the tolerance factor leads to the increase in the
temperature of the ferroelectric-antiferroelectric phase transition, and vice
versa. All obtained results demonstrate the predominant influence of the ion
size factor on the relative stability of the ferroelectric and
antiferroelectric states in the (Na0.5Bi0.5)TiO3-based solid solutions and
indicate the way for raising the temperature of the
ferroelectric-antiferroelectric phase transition.