在层层的二维基协调框架中,通过歇斯底里价值的磁性切换能力
Anthony Lannes1, Yan Suffren2, Jean Bernard Tommasino1
1Univ Lyon, Université Claude Bernard Lyon 1, Laboratoire des Multimatériaux et Interfaces, UMR CNRS 5615, F-69622, Villeurbanne, France.
Journal of the American Chemical Society
|December 13, 2016
概括
一种新的协调聚合物在室温附近表现出独特的温度驱动的价值变化. 这种转变涉及的氧化和激素还原,产生不同的高温和低温形式.
科学领域:
- 协调化学
- 材料科学
- 磁力学
背景情况:
- -氧化化合物以其有趣的磁性特性而闻名.
- 价值复合是一种分子可以存在于不同的电子状态的现象.
- 协调聚合物为探索新的电子行为提供了可调节的结构.
研究的目的:
- 在-氧化物二维协调聚合物中研究异常的歇斯底里热诱导的价值体转变.
- 描述与此过渡相关的结构和电子变化.
- 了解价值复合的机制和温度依赖性.
主要方法:
- 温度依赖的磁性敏感度测量.
- 不同扫描热量计 (DSC).
- 一个单晶X射线衍射.
- 紫外线对吸收光谱
- 射线吸收 (XAS) 和射线发射 (XES) 光谱.
- 电子磁共振 (EPR) 光谱学
主要成果:
- 协调聚合物{[Mn2(NITIm) ]ClO4}n (1) 在室温附近呈现出歇斯底里价值分离过渡.
- 过渡过程涉及氧化Mn{II}到Mn{III},并在冷却 (274K) 时将NITIm基减少为NITRed2并在加热 (287K) 时逆转.
- 多种光谱和热量测量技术证实了不同的高温 (1HT) 和低温 (1LT) 阶段.
结论:
- 这项研究表明,在基于的协调聚合物中,存在一种罕见的歇斯底里的价值变异.
- 这种现象为开发具有可切换磁性和电子性质的材料提供了潜力.
- 观察到的转变突出显示了金属离子还氧化状态和激素连接体在协调系统中的相互作用.
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