一个光磁海绵:通过吸水控制的高温光诱导铁磁体
Michał Magott1, Mateusz Reczyński1, Bartłomiej Gaweł2
1Faculty of Chemistry , Jagiellonian University , Gronostajowa 2 , 30-387 Kraków , Poland.
Journal of the American Chemical Society
|October 31, 2018
概括
这项研究报告了一种新型的光磁体, {[MnII(imidazole) ]2[WIV(CN) 8}n,实现了最高的光诱导磁排序温度. 它的光磁性质与水吸附有关,水化会抑制这种效应.
科学领域:
- 材料科学
- 化学学
- 物理
背景情况:
- 光磁体将光能转化为磁性,这是传统磁性固体中缺失的特性.
- 设计和合成光磁铁具有挑战性,已知示例显示低订单温度.
- 现有的光磁器通常在液沸点以下工作.
研究的目的:
- 合成和描述一种具有增强光磁性能的新型分子化合物.
- 在协调聚合物中研究光诱导磁性和水吸附之间的关系.
- 探索协调聚合物在先进磁性应用中的潜力.
主要方法:
- 一种化物桥接协调聚合物的合成: {[MnII(imidazole) ]2[WIV(CN) 8}n.
- 使用蓝光激发 (450 nm) 的光磁测量.
- 研究水吸附特性及其对磁性行为的影响.
主要成果:
- 该化合物表现出迄今为止最高的光诱导磁性排序温度.
- 观察到高达90K的磁性歇斯底里循环.
- 发现水吸附与光磁功能有很强的相关性,水化消除了光开效应.
结论:
- 这种新型协调聚合物对高温光磁应用具有显著的潜力.
- 吸水和光磁之间的相互作用为材料设计提供了新的途径.
- 可逆水化提供了一种控制和潜在地切换光磁性能的机制.
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