电荷转移辅助相位过渡和慢磁放松功能的调整 (x = 0-9) 分子固体溶液
Szymon Chorazy1,2, Jan J Stanek3, Wojciech Nogaś1
1Faculty of Chemistry, Jagiellonian University , Ingardena 3, 30-060 Kraków, Poland.
Journal of the American Chemical Society
|January 14, 2016
概括
这项研究合成了具有可调节磁性质的新型铁集群. 铁与离子的比率控制电荷转移,相位过渡和磁放松,从而能够精确控制材料的功能.
科学领域:
- 无机化学
- 材料科学
- 磁化学
背景情况:
- 桥协调化合物提供可调节的电子和磁性特性.
- 基于集群的分子固体为设计具有特定功能的材料提供了一个平台.
- 控制混合金属集群中的金属离子比率是调整它们的关键.
研究的目的:
- 合成一系列具有不同铁-比的同结构{Fe(9-x) Co(x) [W(CN) 8) 6 ((MeOH) 24}·12MeOH集群.
- 研究受控的C/Fe静态测量对这些集群的磁性功能的影响.
- 阐明电荷转移,相位转换和磁放松现象之间的关系.
主要方法:
- 在甲醇中,Co{2+},Fe{2+}和[W{V}}CN{8}{3-}的固态组合.
- 具有六顶体中心立方体拓的五十核集群的结构特征.
- 分析电荷转移,旋转交叉和磁放松的光谱和磁性研究.
主要成果:
- 一系列同结构的{Fe(9-x) Co(x) [W(CN) 8) 6(MeOH) 24}·12MeOH集群 (x=0-9) 已成功合成.
- 富含铁的相 (0-5) 呈现与电荷转移 (CT) 和旋转交叉 (SCO) 相关的热诱导可逆结构相变 (180-220 K).
- 富含的阶段 (6-9) 显示缓慢的磁放松,随着含量增加,磁放松的能量障碍会增加.
结论:
- 这些集群中的Co/Fe比率允许前所未有的磁性功能调整.
- 铁-NC-W连接促进相位过渡,而Co-W CTIST增强结构变化和磁性歇斯底里.
- 这些基于集群的分子固体溶液代表了一类独特的材料,具有可调节的磁性行为,用于高级应用.
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