格子溶剂工程提高了金化铁磁链的稳定性
Rafael A Allão Cassaro1, Paul M Lahti2, Maria G F Vaz3
1Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-909, Brazil.
Inorganic chemistry
|July 6, 2023
概括
合成了一种新的1D铁磁复合物Co-PyrNN·bf·hep,表现出硬磁特质和缓慢的磁放松. 与类似的基化合物相比,其稳定性得到了增强,证明了格子溶剂对单链磁体的影响.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 单链磁铁 (SCM) 是具有缓慢磁性放松的分子材料.
- SCM的稳定性对于其实际应用至关重要.
- 兰化物和过渡金属复合物经常被研究SCM特性.
研究的目的:
- 为了合成和表征一种新的1D铁磁复合物,使用氧化基.
- 研究合成复合物的磁性特性,包括放松和歇斯底里.
- 为了比较合成复合物的稳定性与以前报告的类似化合物.
主要方法:
- 2-(1'-pyrenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (PyrNN) 与 [Co(hfac) 2 ((H2O) 2 ] 在 n-heptane 和 bromoform 中的反应.
- 单晶X射线衍射用于结构确定.
- 测量磁敏度和放松度 (直流和交流磁力测量).
主要成果:
- 1D铁磁复合物的形成 [Co(hfac) 2PyrNN]·0.5bf·0.5hep (Co-PyrNN·).
- 观察缓慢的磁放松与磁阻断低于13.4K.
- 用高强制场 (51kOe在5.0K) 展示磁性歇斯底里,将其归类为硬磁体.
- 确定激活屏障,以放松 (365 ± 24) K. 的活性屏障.
- 这种含有形式的化合物是之前报告的含有形式的类似物的一种同型和更稳定的变体.
结论:
- 合成的Co-PyrNN·复合体表现出有希望的硬磁特征和缓慢的磁放松.
- 选择的格子溶剂 (形与形) 显著影响这些单链磁铁的稳定性.
- 这项研究强调了溶剂工程在设计稳定的分子磁性材料中的重要性.
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