Nv. Dergunova et al., On the possibility of isomorphic substitutions in ferroelectrics with the perovskite- and pseudoilmenite-type structure, FERROELECTR, 247(1-3), 2000, pp. 107-124
The present paper deals with a crystallochemical analysis of the possibilit
ies of isomorphic substitution of atoms in the ferroelectrics (Na, Li) NbO3
and LiNbO3 with a perovskite- and pseudoilmenite-type structure, respectiv
ely. As the arguments we used dimension, electronegativity, electron struct
ure and symmetry of valent orbitals of the substituted and substituting ato
ms. The solid solutions (SS) of binary systems on the basis of LiNbO3 (or N
aNbO3) and iso- and nonisostructural components and also the compositions o
f (Na, Li) NbO3 and lithium metaniobate (LMN) modified with n-valent (n = 1
- 6) elements were chosen as the objects of the present study. Diagrams of
solubilities for substitutions in the A- or B- sublattice of (Na, Li)NbO3
and LiNbO3 were constructed. The original experimental results and the bibl
iographical data confirming the correctness of the analysis a presented.