五坐标坐标复合体中的磁场诱导的缓慢磁放松:通过化物替代调整磁异性
Hong-Yao Guo1, Wei-Quan Lin1, Ji-Dong Leng1
1School of Chemistry and Chemical Engineering/Institute of Clean Energy and Materials, Guangzhou Higher Education Mega Center, Guangzhou University, No. 230 Wai Huan Xi Road, Guangzhou 510006, China.
研究人员合成并研究了具有独特磁性特性的三种 (II) 复合物. 这些五坐标复合体表现出缓慢的磁放松,受化物联体电负性的影响.
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:
- 五坐标 (pentacoordinate cobalt) 复合物由于其多样化的磁性行为而引起人们的兴趣.
- 双酸联体1,2-bis(二酸) (dppb) 可以稳定各种协调几何形状.
- 化物联体在调节金属复合物的电子和磁性质方面发挥着至关重要的作用.
研究的目的:
- 合成和表征新的五坐标 ((II) 复合物.
- 研究这些复合物的结构和磁性特性.
- 了解化物连接体对磁性异构和放松动态的影响.
主要方法:
- 合成三种五坐标 ((II) 复合物:[CoX ((dppb) ]2]X (X = Cl, Br, I). 这三种复合物的合成方法是:
- 单晶X射线衍射用于结构确定.
- 测量磁性易感度和放松度,以探测磁性.
主要成果:
- 这三种复合体都采用空八面体 (C4v) 几何形状,其化物联体处于轴向位置.
- 复合体表现出磁场诱导的缓慢磁放松.
- 阳性D值表明显著的磁性异构性,随着化物电负率的下降而下降 (25.3(2) cm−1对于Cl,21.6(1) cm−1对于Br,19.4(2) cm−1对于I).
- 拉曼过程在较高温度下主导磁放松.
结论:
- 合成的 (II) 复合体表现出特有的慢磁放松行为.
- 磁性异构性和放松动力学受到化物连接体性质的系统影响.
- 这些发现有助于理解协调复合体中的单分子磁铁行为.
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