铁-稀土单分子磁体的设计合成及其磁构关系研究

项目名称： 铁-稀土单分子磁体的设计合成及其磁构关系研究

项目编号： No.21501093

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 彭国

作者单位： 南京理工大学

项目金额： 20万元

中文摘要： 单分子磁体在高密度信息储存、量子计算、自旋电子器件等方面具有潜在的应用价值。高的自旋和显著的磁各向异性是产生单分子磁体的两个必要条件。铁离子具有较高的自旋，而重稀土离子呈现出显著的磁各向异性，所以把两者有机地结合到一个配位簇合物中有助于提高得到单分子磁体的概率，但是铁-稀土单分子磁体的阻塞温度和有效能垒还比较低，而且稀土离子的引入增加了其磁构关系理解的难度。本项目拟利用多甘醇为配体，有机羧酸为辅助配体来实现铁-稀土配位簇合物的组装，探索通过铁-稀土离子之间桥连基团的改变和辅助配体的取代来增强铁-稀土离子之间的交换作用和改变体系中稀土离子的磁各向异性，从而提高铁-稀土单分子磁体的阻塞温度和有效能垒。与此同时，通过穆斯堡尔能谱对体系中稀土离子的磁各向异性进行研究，探讨稀土离子的磁各向异性在铁-稀土单分子磁体中发挥作用的机制，进而加深对铁-稀土单分子磁体磁构关系的理解。

中文关键词： 铁；稀土；单分子磁体；穆斯堡尔能谱；磁各向异性

英文摘要： Single molecule magnets (SMMs) have potential applications in high-density information storage, quantum computing and spintroic devices. One compound can be described as SMM when it possesses large spin ground state and magnetic anisotropy. The iron ions can offer high spin, while the heavy lanthanide ions present large magnetic anisotropy, thus the combination of iron and lanthanide ions in one coordination cluster increases the chance to obtain SMM behavior. However, the blocking temperature and the energy barrier of iron-lanthanide SMMs are still very low and the incorporation of lanthanide ions in iron-lanthanide coordination clusters increases the difficulty in understanding the magneto-structural relationship of the resulting compounds. The goal of this project is to prepare iron-lanthanide coordination clusters by employing polyethylene glycol as ligand and carboxylic acid as co-ligand, and then to improve the blocking temperature and energy barrier of iron-lanthanide SMMs by enhancing the interactions between iron and lanthanide ions and tuning the magnetic anisotropy of lanthanide ions via changing the bridging groups between iron and lanthanide ions and the substitution of co-ligand. Furthermore, the contribution of magnetic anisotropy of lanthanide ions in iron-lanthanide SMMs will be explored by using Mössbauer spectroscopy, which will lead to the better understanding of the magneto-structural relationship of iron-lanthanide SMMs.

英文关键词： iron;lanthanide;single molecule magnet;Moessbauer sepctroscopy;magnetic anisotropy