4f-π分子混合体表现出丰富的导电相和缓慢放松的磁化
Yongbing Shen1, Goulven Cosquer2, Haitao Zhang3
1Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-Ku, Sendai 980-8578, Japan.
Journal of the American Chemical Society
|June 22, 2021
概括
这项研究引入了一种具有磁性和电导性的新型分子混合材料. 这种材料显示了温度依赖的导电相和磁放松,为先进的磁器件铺平了道路.
科学领域:
- 材料科学
- 凝聚物质物理学
- 化学学
背景情况:
- 单分子磁铁与电导性之间的合作对于开发高密度磁器件至关重要.
- 关于结合这些特性的材料的报道很少,这凸显了当前研究的差距.
研究的目的:
- 报告一种基于4f-π的新型分子混合体, *k*-(ET) 5Dy(NCS) 7(KCl) 0.5 (1),表现出缓慢的磁化放松和电导性.
- 在这种混合材料中研究分子结构,电子电荷和磁性行为之间的相互作用.
主要方法:
- 合成和特征的 * k * - ET) 5 Dy) 7 KCl) 0.5 (1) 分子混合物.
- 在75-300K的温度范围内测量电导率.
- 使用计算方法分析电子结构.
- 在4K以下的磁感应和放松测量.
主要成果:
- 混合材料具有75-300K之间的明显相位的温度敏感电导率.
- 观察到一种金属状态,其特点是导电性和歇斯底里性上升,归因于部分氧化ET电荷 (接近0.5+).
- 电子结构计算证实了冷却后孔度的增加,与部分氧化相一致.
- 较弱的抗铁磁相互作用和低于4K的双磁放松过程与4f-π相互作用有关.
结论:
- 合成的分子混合体显示出有前途的合作磁性和导电性质.
- 材料丰富的导电相和金属行为是由温度依赖的电荷状态驱动的.
- 观察到的磁现象与弱4f-π相互作用有关,这表明分子自旋学的潜力.
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