醇胺簇基磁性材料的磁学性质调控与开关效应研究

To meet with the new requirement for the magnetic materials raised by the rapidly developing science and technology in nowadays, the properly selected or designed amino alcohol ligands bearing non-coordinating groups are to be synthesized or used directly in this project to prepare transition metal clusters, lanthanide clusters and transition metal-lanthanide hetrometallic clusters with the ligand field strengths of their metal ions being controllable. Our aim is to switch their magnetic properties reversibly under control by switching their structures reversibly. To achieve this, the structures and magnetic properties of the aimed clusters could be tuned by the selection of proper coordinating groups and appropriate non-coordinating groups, as well as by some ancillary ligands and some diamagnetic metal ions, which might lead to a critical state for the ligand field strengths of the metal ions in the clusters. Then different kinds of physical or chemical methods are to be explored to alter the nature or strengths of the ligand field of the metal ions, which can achieve the aim of switching the magnetic properties of the clusters by changing the structures of the cluster reversibly and the spin states of the metal ions, as well as by changing the nature and strengths of magnetic interactions between metal ions. A systematic study is planned to explore all kinds of magnetic switches induced by different types of reversible structural transformation with the aim of developing new types of magnetic materials, which would contribute significantly on the applications in molecular level such as information storage, magnetochemical sensor and spintronics.

基于现代科学技术的快速发展对磁性材料提出的新要求，我们拟选用或设计合成含非配位基团的醇胺类配体，合成配体场强度可控的过渡金属簇合物、镧系金属簇合物及过渡金属-镧系金属杂金属簇合物，以簇合物结构的可逆转变调控其磁学性质的可逆转变，实现簇合物磁学性质的可控开关。根据所选顺磁金属离子，通过配体上配位基团的选择与非配位基团的调节或辅以必要的辅助配体与抗磁金属离子来调控簇合物的结构与磁学性质，使其中金属离子的配体场强度处于可控的临界状态，探索各种物理的或化学的方法可逆改变配体场种类或强度，达到可逆调控簇合物结构及其金属离子的自旋状态或磁交换种类与强度，实现可逆调控簇合物磁学性质之目的。系统研究各种类型的结构可逆变化导致的磁学性质开关效应，开发新型磁性材料，为磁性材料在分子水平的信息存储、磁化学传感器、自旋电子学等方面的应用奠定基础。

基于现代科学技术的快速发展对磁性材料提出的可控开关新要求，我们选用和设计合成一系列含非配位基团的醇胺类配体及其席夫碱，合成了84种配体场强度可控的过渡金属簇合物、镧系金属簇合物及过渡金属-镧系金属杂金属簇合物。以簇合物结构的可逆转变调控其磁学性质的可逆转变，实现簇合物磁学性质的可控开关。根据所选顺磁金属离子，通过配体上配位基团的选择与非配位基团的调节或辅以必要的辅助配体与抗磁金属离子来调控簇合物的结构与磁学性质，使金属离子的配体场强度处于可控的临界状态，探索各种物理的或化学的方法可逆改变配体场种类或强度，达到可逆调控簇合物结构及其金属离子的自旋状态或磁交换种类与强度，实现可逆调控簇合物磁学性质之目的。系统研究了各种类型的结构可逆变化导致的磁学性质开关效应，开发新型磁性材料，为磁性材料在分子水平的信息存储、磁化学传感器、自旋电子学等方面的应用奠定基础。筛选出三种不含结晶溶剂分子的线型三核钴簇合物，通过升温与降温进行单晶到单晶转换，达到通过簇合物分子的堆积方式调控磁学性质可逆转变之目的。以异丁醇胺为配体筛选出四个异质同晶的二十四核杂金属簇合物，通过结晶溶剂分子及卤素离子的可逆得失实现磁学性质的可逆调控。以三羟甲基氨基甲烷为配体筛选出三例五核簇基杂金属分子基磁体Cu3Ln2，通过结晶溶剂分子的可逆得失实现分子基磁体的开关调控。以1,3–二氨基–2–丙醇做配体筛选出一系列Cu3Ln簇基单分子磁体，通过端式配位分子的失去实现四核簇合物Cu3Dy到双聚成八核簇合物Cu6Dy2的固态转变，实现磁学性质上从双慢磁驰豫到单慢驰豫的调控。部分研究结果已在J. Mater. Chem. C, Inorg. Chem., Dalton. Trans.等国际SCI刊物上发表14篇具有一定影响力的论文（二区及二区以上论文11篇），申请发明专利4项，已获授权3项。培养硕士研究生9名，博士研究生3名（在读），为社会输送高水平人才。