a four-layer Aurivillius structure with the orthorhombic lattice (unit cell parameters: a = 5.4300(2) A, b = 5.4451(7) A, c = 41.2800(6) A; space group A2 1 am (36)). Temperature dependent electrical and magnetic properties of the material have been investigated and compared to those of Bi 5 FeTi 3 O 15 . The relative permittivity maximum and divergence of loss tangent, observed at 970 K, is attributed
摘要 通过传统的固态高温合成方法成功制备了一种具有Bi 5− x Th x Fe 1+ x Ti 3− x O 15 ( x = 1/3) 组成的新型Aurivilius氧化物。X射线衍射证实该材料是严格单相的,具有正交晶格的四层Aurivilius结构(晶胞参数:a = 5.4300(2) A, b = 5.4451(7) A, c = 41.2800( 6) A;空间群 A2 1 am (36))。已经研究了该材料的温度相关的电学和磁学性质并将其与Bi 5 FeTi 3 O 15 的那些相比较。在 970 K 观察到的相对介电常数最大值和损耗角正切的发散归因于
铁电到顺电的相变。在低温下,该材料表现出具有短程反
铁磁耦合的顺磁行为。Fe K-edge XAFS 光谱分析表明,Bi 5− x Th x Fe 1+ x Ti 3− x O 15 ( x = 1/3) 中的Fe-O 距离更短,Fe