First Structural and Magnetic Studies of Ni Clusters Containing 2,6-Diacetylpyridine-dioxime as a Ligand

In the present work, coordination possibilities of the system dapdoH2/Ni2+, being dapdoH2 = 2,6-diacetylpyridine dioxime, have been explored, offering as a result a number of unprecedented clusters with a variety of topologies and magnetic behaviors. Depending on the precursors and reaction conditions, several compounds named [Ni2(dapdo)2] (1), [Ni3(OH)(BzO)3(dapdo)(dapdoH2)(H2O)]·1.25H2O (2), [Ni3(AcO)4(dapdoH)2(H2O)2]·H2O (3), and [Ni4(AcO)3(dapdo)(dapdoH)2(H2O)3]·(AcO)·3H2O (4) were achieved and structurally well-characterized. Dc magnetic measurements were carried out in the 2−300 K range revealing antiferromagnetic interactions for (2−4) compounds and diamagnetic response for the square planar coordinated complex (1).

本研究探究了dapdoH2/二价镍离子（Ni²+）体系的配位可能性，其中dapdoH2即2,6-二乙酰吡啶二肟（2,6-diacetylpyridine dioxime），最终得到一系列具有多样拓扑结构与磁学行为的前所未有的金属簇合物。通过调控前驱体种类与反应条件，我们成功合成了四种配合物，分别为[Ni₂(dapdo)₂]（1）、[Ni₃(OH)(苯甲酸根,benzoate,BzO)₃(dapdo)(dapdoH₂)(H₂O)]·1.25H₂O（2）、[Ni₃(乙酸根,acetate,AcO)₄(dapdoH)₂(H₂O)₂]·H₂O（3）以及[Ni₄(AcO)₃(dapdo)(dapdoH)₂(H₂O)₃]·(AcO)·3H₂O（4），并对所有产物完成了完整的结构表征。直流磁学测试在2~300 K的温度范围内开展，测试结果显示，配合物2至4均存在反铁磁相互作用，而平面正方形配位的配合物1则表现出抗磁响应。