Intrinsic reasons for variations in dielectric properties of Ba6-3x R8+2x Ti18O54(R = La-Gd) solid solutions

被引：83

作者：

Valant, M ^{[1
]}

Suvorov, D ^{[1
]}

Rawn, CJ ^{[1
]}

机构：

[1] Jozef Stefan Inst, Ljubljana 1000, Slovenia

来源：

JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS | 1999年 / 38卷 / 5A期

关键词：

Ba6-3xR8+2xTi18O54 solid solutions; microwave ceramic; dielectric properties; octahedral tilt; tungsten bronze; perovskite;

D O I：

10.1143/JJAP.38.2820

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Studies Of the temperature coefficient of permittivity of Ba6-3xR8+2xTi18O54 (R = La-Gd) solid solutions revealed a high degree of correlation with the ratio of mean radii (gamma(A)/r(B)) Of A- and B-site ions. Single-crystal X-ray diffraction analyses of La, Sm and Pr analogues showed that r(A)/r(B) can be further correlated to tilting of the TiO6 octahedra in the network of the Ba8-3xR8+2xTi18O54 crystal structure. Changes in the rating of the octahedra induce changes in the crystal field and subsequently, changes in the temperature coefficient of permittivity as well as dielectric loss. Variations in dielectric properties are limited by the flexibility of the crystal structure. Variations in the tilting of the octahedra resulting from changes in the composition are highly anisotropic, which explains the markedly high electrical anisotropy of Ba6-3xR8+2xTi18O54 solid solutions.

引用

页码：2820 / 2826

页数：7

共 26 条

[1] TEMPERATURE DEPENDENCE OF DIELECTRIC CONSTANTS OF CUBIC IONIC COMPOUNDS [J].