高核过渡金属取代的夹心型锗钼酸盐的合成与磁性研究

In this project, new high-nuclear sandwich-type germanomolybdates based on trivacant Keggin polyoxoanions will be prepared using conventional syntheses, liquid phase diffusion syntheses and hydrothermal syntheses. In addition, novel organic-inorganic sandwich-type germanomolybdates with multi-dimensional structures will be also synthesized through the bridging of organic ligands. In order to obtain the compounds with different interactions and single molecule magnet behaviors, some paramagnetic metal cations will be introduced to the reaction system. Then, these compounds will be characterized by elemental analyses, IR，UV spectroscopy,X-ray powder and X-ray single crystal diffraction. Their thermal stabilities and redox properties will be studied using thermal analyses and electrochemical analyse, respectively. In order to provide new methods for the design and syntheses of novel sandwich-type heteropolymolybdates, the factors influencing the nuclear numbers of the sandwiched layer will be researched. The magnetism properties of the compounds will be characterized and calculated by Quantum Chemistry Simulation. Then the correlation of their structures and magnetism properties will be studied. The project will provide theoretic and experimental basis for the magnetism study of other sandwich-type heteropolymolybdates. At last, the project will exploit especial magnetism materials to widen the application field of sandwich-type heteropolymolybdates.

本项目拟通过常规合成法、液相扩散合成法和水热合成法，制备基于三缺位Keggin结构阴离子形成的高核夹心型锗钼酸盐。通过有机配体的桥连，构筑具有多维结构的有机-无机夹心型锗钼酸盐。在反应体系中引入顺磁性金属阳离子，以期获得具有不同磁相互作用及单分子磁体行为的化合物。利用元素分析、IR、UV光谱、X-射线粉末衍射及X-射线单晶衍射等手段对化合物进行结构测定及表征。通过热分析和电化学手段研究化合物的热稳定性和氧化还原性。研究影响化合物夹心层核数的因素，为新型杂多钼酸盐的设计、合成提供新方法。对化合物进行磁性质测试及量子化学模拟计算，探索结构和磁性之间的关系，为其它夹心型杂多钼酸盐的磁性研究提供实验依据和理论基础。开发具有磁功能特性的材料，拓宽夹心型杂多钼酸盐的应用领域。

基于羧基配体构筑的多金属氧酸盐多集中于羧酸修饰的同多氧酸盐，而羧酸构筑的杂多氧酸盐少有报道。本项目通过常规合成法和水热合成法，选择不同的多金属氧酸盐前驱体，在不同结构的羧基配体调控下，制备了多系列的有机-无机杂多钼酸盐、杂多钨酸盐化合物，并对其进行了元素分析、红外光谱、紫外光谱、热分析、X-射线粉末衍射和X-射线单晶衍射测试，探索了不同羧基配体对结构的影响，并对其光学和磁学性能进行了研究。本项目的研究，不仅可以丰富该类化合物的立体化学，而且为开发新的光学、磁学材料提供了理论基础。