Cooperative dielectric interaction of the perovskite-related layered solid solution system Sr_n+1(Sn_xTi_1-x)_nO_3n+1 (n = 1, 2 and ∞)

Abstract

In the viewpoint of cooperative interaction of BO₆ octahedra, structure change and dielectric property of the Sr_n-1(Sn_xTi_1-x)_nO_3n+1 (n = 1, 2 and ∞) solid solution system having Ruddlesdon-Popper type layer structure have been investigated as a function of x. The crystal symmetry of the Sr₃(Sn_xTi_1-x)_{2 2}O₇ series shows tetragonal in the range x ⩽ 0.50 and orthorhombic in x ⩾ 0.75, while that of Sr(Sn_xTi_1-x)O₃ and Sr₂(Sn_xTi_1-x)O₄ series with x becomes cubic and tetragonal, respectively. The samples in the compositions of 0.00 ⩽ x ⩾ 0.50 for n = 1 and 2, and 0.00 ⩽ x ⩾ 0.75 for n = ∞ show a quantum paraelectric behavior, while in other composition range, sample shows a positive temperature coefficient of dielectric constant. With increasing the concentration of the TiO₆ octahedra in the same n compositions, the dielectric constant intensively increases. The results are discussed in terms of the cooperative interaction that occurs mainly through collinearly corner-shared the TiO₆ octahedra and among the nearest neighbor octahedra.

Keywords:

• Dielectric property
• [TiO₆] octahedra
• dielectric cooperative interaction
• Sr_n+1(Sn_xTi_1-x)_nO_3n-1
• Ruddlesdon-Popper type layered structure