尼克尔中场诱导的单离子磁铁行为 (II) 复合物与功能化2,2':6'-2" - 二衍生物:制备和磁铁结构研究
Francisco Ramón Fortea-Pérez1, Julia Vallejo1, Teresa F Mastropietro2
1Instituto de Ciencia Molecular (ICMol), Departament de Química Inorgànica, Universitat de València, 46980 Paterna, Spain.
Molecules (Basel, Switzerland)
|June 10, 2023
概括
两个新的 (II) 复合体表现出单分子磁铁行为. 这些复合体显示磁化由于轴向压缩缓慢放松,这是场诱导的单分子磁体现象的特征.
科学领域:
- 协调化学 协调化学
- 磁电化学 磁电化学 磁电化学
- 材料科学 材料科学 材料科学
背景情况:
- (II) 复合物被研究其磁性特性.
- 二连接物是协调化学中的多功能构建块.
- 单分子磁铁 (SMM) 对量子计算和数据存储的潜在应用很有兴趣.
研究的目的:
- 合成和表征两个新型单核 (II) 复合体.
- 为了研究磁性特性,并了解单分子磁铁行为的起源.
- 为了将结构特征与观察到的磁现象相关联.
主要方法:
- 单晶X射线衍射用于结构确定.
- 可变温度直流 (dc) 磁感应度测量.
- 交流电流 (ac) 磁感应度测量和磁化研究.
- 理论计算以支持实验发现.
主要成果:
- 合成了两个单核 (II) 复合物,即[Ni (terpyCOOH) ]2[ClO4) 2·4H2O (1) 和[Ni (terpyepy) ]2[ClO4) 2 MeOH (2),并进行了结构性特征.
- 磁性研究揭示了在高温下库里定律的行为以及零场分裂的证据 (D = -6.0 cm-1对1,D = -4.7 cm-1对2).
- 这两种复合体在电感度测量中都显示出初始的外相信号,这表明了 induced 场诱导的单分子磁体行为,归因于 (II) 协调球的轴向压缩.
结论:
- 合成的 (II) 复合体表现出场诱导的单分子磁体行为.
- 在(II) 离子的八面体环境中的轴向压缩导致负零场分裂值,这对于SMM属性至关重要.
- 观察到的磁化缓慢放松可以通过奥巴赫和直接机制的组合来解释.
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