在V2OPO4中的电荷顺序和负热膨胀
Elise Pachoud1, James Cumby1, Calum T Lithgow1
1Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh , Edinburgh EH9 3FD, United Kingdom.
Journal of the American Chemical Society
|December 21, 2017
概括
半等效氧化V2OPO4具有高达605K的电荷,显示结构过渡和热膨胀的切换. V-V 粘合损失驱动了这种新的行为,与164 K以下的铁磁顺序一起.
科学领域:
- 固态化学
- 材料科学
- 磁性
背景情况:
- 了解收费订单及其对材料属性的影响至关重要.
- 研究可切换热膨胀的新材料具有重大意义.
研究的目的:
- 研究半等效氧化V2OPO4的电荷排序和热膨胀特性.
- 阐明V-V结合,结构转换和热膨胀行为之间的关系.
- 为了探索V2OPO4中的磁性排序.
主要方法:
- 用X射线衍射进行结构分析.
- 用于测量热膨胀的扩展度.
- 在磁性排序研究中测量磁性易感性.
主要成果:
- 观察到长距离V2+/V3+充电顺序高达605K.
- 在605K时单临床到四角结构的过渡.
- 观察到从正向负的热膨胀.
- 在164K下磁顺序过渡的铁磁顺序.
- 在较高的温度下发现局部旋转配对的证据.
结论:
- 轨道聚合物链中的V-V结合是可切换热膨胀的关键.
- 在高温下,V-V结合的损失使横向氧气运动主导热膨胀.
- V2OPO4在电荷排序,结构和磁性之间表现出复杂的相互作用.
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