氧基化物A2F2Fe2OQ2 (A = Sr,Ba;Q = S,Se) 的结构和磁性特性,Fe2O的方形平面层代表了反铁磁的棋盘旋转网格
Houria Kabbour1, Etienne Janod, Benoît Corraze
1Institut des Matériaux Jean Rouxel, CNRS-Université de Nantes, 2 rue de la Houssinière, BP32229, 44322 Nantes, France.
Journal of the American Chemical Society
|June 7, 2008
概括
合成了新的磁性半导体,A2F2Fe2OQ2,具有抗CuO2层. 这些材料表现出反铁磁的顺序,并代表了一种罕见的反铁磁棋盘格子.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 具有抗CuO2结构图案的氧化基因因因其独特的电子和磁性特性而引起兴趣.
- 分层二级建筑单元为设计新型无机化合物提供了模块化方法.
研究的目的:
- 预测和合成新型氧基化物A2F2Fe2OQ2.2.
- 描述这些新化合物的物理性质和磁相互作用.
- 为了研究它们作为受挫的磁性材料的潜力.
主要方法:
- 分层二级建筑单元的模块化组装用于预测.
- 合成A2F2Fe2OQ2化合物 (A = Sr,Ba;Q = S,Se) 的方法.
- 通过磁感应,电电阻,比热, (57) Fe Mossbauer光谱和粉末中子衍射进行表征.
- 第一个原则密度函数理论 (DFT) 用于电子结构和交换相互作用计算.
主要成果:
- 成功合成了A2F2Fe2OQ2氧基化物.
- 被识别为磁性半导体的化合物具有83.6-106.2 K.之间的远程反铁磁顺序.
- 两个维的伊辛格模型准确地描述了磁性特性.
- 通过共享角的Fe-O-Fe桥梁进行主导的反铁磁旋转交换.
- DFT的计算证实了一种罕见的反铁磁棋盘格子.
结论:
- A2F2Fe2OQ2化合物是新的磁性半导体,在自旋电子学中具有潜在的应用.
- 观察到的丧的反铁磁棋盘格子是基本磁性研究的一个重要发现.
- 模块化组装方法对于设计复杂的分层材料是有效的.
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