Xia Zhengyao, Li Yan, Ji Cheng, Jiang Yucheng, Ma Chunlan, Gao Ju, Zhang Jinlei
Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application, School of Physical Science and Technology, Suzhou University of Science and Technology, Suzhou 215009, China.
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
Nanomaterials (Basel). 2022 Feb 21;12(4):707. doi: 10.3390/nano12040707.
Co(II) mononuclear complex with different coordination geometry would display various of field-induced single-ion magnet (SIM) behaviors. Here, we identify a field-induced single-ion magnet in a mononuclear complex Co(HDPA)·HO (HDPA = 2,6-pyridine-dicarboxylic acid) by the hydrothermal method. The long axial Co-O coordination bond (Co1‧‧‧O3) can be formed by Co1 and O3. Therefore, Co(II) ion is six-coordinated in a distorted elongated octahedron. AC magnetization susceptibilities show that the effective energy barrier is up to 43.28 K. This is much larger than most mononuclear Co(II). The distorted elongated octahedron caused by the axial Co-O coordination bond is responsible for the high effective energy barrier. The distribution of electron density in Co1 and O3 atoms in the long axial bond would influence the magnetic relaxation process in turn. Our work deepens the relationship between the effective energy barrier and the weak change of ligand field by long axial bonds, which would facilitate constructing SIM with high energy temperature.
具有不同配位几何结构的钴（II）单核配合物会表现出各种场诱导单离子磁体（SIM）行为。在此，我们通过水热法在单核配合物Co(HDPA)·H₂O（HDPA = 2,6 - 吡啶二甲酸）中识别出一种场诱导单离子磁体。长轴方向的Co - O配位键（Co1∙∙∙O3）可由Co1和O3形成。因此，Co（II）离子在扭曲的拉长八面体中呈六配位。交流磁化率表明有效能垒高达43.28 K。这比大多数单核钴（II）配合物要大得多。由轴向Co - O配位键导致的扭曲拉长八面体是高有效能垒的原因。长轴键中Co1和O3原子的电子密度分布会反过来影响磁弛豫过程。我们的工作深化了有效能垒与长轴键引起的配体场微弱变化之间的关系，这将有助于构建具有高能量温度的单离子磁体。
