在一个微弱的Jahn-Teller d2cation中具有高度稳定的合作扭曲:通过高压和高温转化从比克斯拜中获得的矿类型ScVO3
Elizabeth Castillo-Martínez1, Mario Bieringer, Shahid P Shafi
1Departamento de Química Inorgánica & Laboratorio Complutense de Altas Presiones, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain. ilaisza@hotmail.com
Journal of the American Chemical Society
|May 18, 2011
概括
在高压和高温下合成了一种新的瓦纳酸 (ScVO(3)) 矿阶段. 这种新型材料具有独特的结构,电和磁性,包括Jahn-Teller扭曲和反铁磁排序.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 矿氧化物在各种技术应用中至关重要.
- 了解新型矿的结构性质关系对于材料开发至关重要.
- 瓦纳酸 (ScVO(3)) 已显示出复杂的相位行为.
研究的目的:
- 合成和表征一种新的ScVO(3) 矿阶段.
- 为了研究它的结构,电气和磁性特性.
- 了解合成条件对矿形成的影响.
主要方法:
- 高压和高温合成 (8 GPa,1073 K).
- 在室温和低温下进行结构分析的X射线衍射.
- 电导率测量. 电导率测量. 电导率测量. 电导率测量. 电导率测量.
- 测量磁感应度的测量.
主要成果:
- 成功合成了一种新型的正方体 ScVO(3) 矿相 (空间组 Pnma).
- 该结构的特点是有序的Sc(3+) 和V(3+) 离子和合作的Jahn-Teller扭曲.
- 电导率遵循阿雷尼乌斯类型的行为.
- 在90K附近,结构过渡到三临床对称 (空间组P-1) 发生.
- 在60K以下观察到磁时刻的反铁磁远距离排序,形成一个特定的磁性超结构.
结论:
- 一个新的ScVO(3) 矿相的合成扩大了已知的酸盐材料的范围.
- 观察到的Jahn-Teller扭曲和磁顺序凸显了结构和电子特性之间的复杂相互作用.
- 这种材料有可能在需要特定磁性和电性特征的领域进行进一步研究.
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