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在8坐标Mn(II) 化合物中缓慢的磁放松
Li-Xin Wang1,2, Xiao-Fan Wu3, Xin-Xin Jin3
1Key Laboratory of Optoelectronic Chemical Materials and Devices (Ministry of Education), School of Optoelectronic Materials and Technology, Jianghan University, Wuhan, 430056, China. xiangjing@yangtzeu.edu.cn.
Dalton transactions (Cambridge, England : 2003)
|October 9, 2023
概括
这项研究引入了四种新的 (II) 化合物,它们具有缓慢的磁放松. 这些单分子磁铁 (SMM) 尽管具有小的负D值,但仍显示出潜力,扩大了高旋转Mn2SMM的领域.
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:
- 基于高旋转的单分子磁铁 (SMM) 的开发落后于其他第一排过渡金属.
- 之前在设计Fe(II),Co(II) 和Fe(III) SMM中取得的成功,其协调号为8,这项工作得到了启发.
研究的目的:
- 设计和合成具有8的高协调数的新型Mn{\displaystyle Mn{\text{II}}) 类似物.
- 为了研究这些新的Mn2化合物的磁性特性和缓慢的磁放松行为.
主要方法:
- 合成四种Mn(II) 化合物,使用四丹酸联体 (L1-L4) 和化Mn(II) 甲酸盐.
- 通过X射线晶体学确定晶体结构,以确认协调号.
- 磁性特性调查,包括在直流电场下慢磁放松的分析.
主要成果:
- 成功合成了四种新的MnII) 化合物[MnII]Ln) 2]ClO4) 2 (1-4).
- 在所有化合物中,X射线结晶学证实了Mn (II) 中心的过和协调数为8.
- 所有合成的Mn(II) 化合物都表现出缓慢的磁放松行为,即使是小的负D值.
结论:
- 设计高协调数复合体的策略对于开发基于Mn{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}{\displaystyle Mn}}
- 合成的二化合物显示出有希望的缓慢磁放松,有助于二SMM研究的进步.
- 为了发现新的SMM,需要对具有高协调数的Mn2复合体进行进一步的勘探.
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