基于肟-多唑混合配体含不对称磁格的分子基磁材料的合成与磁性能研究

The synthesis and preparation of multi-step magnetic transition coordination complexes have recently becoming one of attracting intense interest due to their promising applications as efficient magnetic recording materials.The main content of this project will be focused on the experimental and theoretical investigation on the crystal structures and multi-step magnetic transition behavior of polyzole-oxime mixed ligands based complexes with asymmetric magnetic lattices. We plan to construct the asymmetric magnetic lattices by polyzole template molecules and paramagnetic metal ions, and further disrupt these magnetic lattices by introducing oxime ligands with diverse bridging modes and easily adjusted coordination parameter. And the main purpose is to reveal the effect on geometrical parameter of asymmetric magnetic lattice and multi-step magentic behaviors of target complexes by diversing the number of coordianting groups and the skeleton's size in oxime ligand, number and distribution of nitrogen donors and various substituent in the heterocylic polyzole ligand as well as the nature of the spin carriers. Additionally, as a supplement to the experimental exploration, the proper magnetic model theoretical computations will be performed on the magnetic active subunit to associate the macroscopical the magneto-structural corelationships. We are sure by the project the new methods and experience to achieve the function-oriented design and controllable preparation of molecule-based magnetic materials will be provied, which can significantly promote the development of related subjects.

合成具有不对称磁格的多步磁转变材料不仅有利于人们研究磁体内部复杂的磁竞争机制，而且对高效磁存储材料的制造具有潜在价值。本立项以五元氮杂环多唑作为模板分子与具有不同电子结构的顺磁中心构造不对称磁格，通过引入配位模式多样、配位几何参数容易调控的肟配体调节三唑-金属磁格的对称性及磁格内独立自旋中心的数目，进行多步磁转变材料的设计、合成、结构表征与磁性能测定，揭示肟配体中配位官能团数目、骨架尺寸、侧基种类、多氮唑配体中氮原子数目、分布以及自旋中心的属性对配合物磁格几何参数与复杂磁行为的影响。同时，通过已建立的磁理论模型对不对称磁格内部磁耦合进行分析，探索多步磁转变材料的宏观磁学性能与基元结构参数间的磁-构关系，为实现分子基磁性材料功能导向的结构设计和可控制备提供方法和经验,推动相关学科的发展。

由顺磁金属离子和短桥构筑的此材料引起人们极大兴趣，这不仅因为通过对它的研究可以了解复杂的磁构关系，而且因为这类材料可以在高密度存储材料及量子计算中得到应用。本课题主要合成、表征了以肟及三唑为配体的顺磁金属配合物，并对它们进行了磁行为表征。. 通过与不同金属离子反应，获得了四个基于肟配体的化合物，结构表明CuII与FeII/FeIII化合物均以三核结构为基本构筑单元，构成Cu3、Cu6及FeIIFeIII2结构，其中Cu3与Cu6化合物表现出强的反铁磁与自旋阻错现象。而MnIII配合物由于MnIII离子具有较大的姜泰勒扭曲及抗磁NaI离子的间隔使该配合物表现出慢弛豫行为，这种磁现象可以归结为单离子磁行为。此配合物为肟体系配合物中首例过渡金属单离子磁体。. 通过调整辅助芳香酸种类获得四个基于4-氨基三唑的CuII配合物。这四个配合物均基于线性Cu3三核的一维链结构。不同的链间连接使这四个配合物表现出强反铁磁、顺磁及变磁行为。. 通过将临苯二甲酸与三唑及ZnII盐反应获得一个以棱柱状8核簇为节点的3,12-连接二维配位聚合物，该配合物表现出强的荧光发射和良好的热稳定性。. 通过与不同取代的萘甲酸与CoII盐获得了两个水桥连的CoII链配合物，具有2-萘甲酸的CoII链由于强的链间氢键作用，表现出变磁体行为，而具有1-萘甲酸封端的CoII链由于链间可以忽略的作用，表现出单链磁体行为。