配体场微扰的稀土基单分子磁体及其磁构关系研究

In recent years, single-molecule magnets (SMMs) are attracting particular interest for their vast potential applications, such as memory storage devices, quantum computing technologies. Lanthanide ions are proven to be excellent candidates for the preparation of SMMs because most of them have multiple single electrons and a large spin-orbit coupling. Therefore, studies in lanthanide based SMMs attract widespread concern of scientists from various countries. Now, scientists are probing the subtle effects of structural or electronic variations on SMM characteristics, expecting strategies for the deliberate tuning of SMM properties, finally get SMMs with superior performance. Considering this point, this proposal intends to take ligand field perturbations regulated lanthanide based single molecule magnets (SMMs) and their magnetostructural correlation as the main object of research. The proposal is intended to design and synthesize several appropriate ligands to fabricate lanthanide or mixed lanthanide-transition metal SMMs, furthermore, perturb the ligand field through modifying the ligand substituents and changing the terminal Ligand. Explore the effect of the magnetic interaction between the ligand and lanthanide ions and the interaction between lanthanide ions, including the same substituent/different terminal ligand system and the different substituent/same terminal ligand system. Furthermore, investigate the magnetostructural correlation deeply, providing new design ideas to explore innovative and efficient lanthanide based SMMs.

近年来，单分子磁体已经成为科学家关注的焦点，特别是在高密度信息存储和量子计算机方面的潜在应用。由于稀土离子单电子数多、具有较强的旋轨耦合相互作用，因此稀土离子是制备单分子磁体的理想材料，受到各国科学家的广泛关注。目前，科学家们正致力于磁性与分子结构内在联系的研究，期望通过磁构关系来指导单分子磁体的合成，得到性能优越的单分子磁体。鉴于此，本项目拟以配体场微扰的稀土基单分子磁体及其磁构关系为主要研究对象。本项目拟设计合成几种恰当的配体，通过配体取代基的修饰以及改变不同的端基配体来实现配体场的微扰，合成不同的稀土基单分子磁体。探究相同取代基/不同端基配体、不同取代基/相同端基配体体系中，配体与稀土离子以及稀土离子之间的相互作用对稀土配合物磁性的影响，深入探讨磁构关系，为发掘新颖高效的稀土基单分子磁体提供新的设计思路。

由于稀土离子的特殊性质，稀土基单分子磁体的研究已经成为科学家关注的焦点，特别是在高密度信息存储和量子计算机方面的潜在应用。我们在国家自然基金（21501043）的支持下，开展了相关课题的研究，历经三年时间取得了初步研究成果，主要内容总结如下：.（1）本项目设计合成了14种希夫碱配体，并利用这些配体和不同的β-二酮端基配体反应，制备了42个稀土双核、四核簇，其中单分子磁体18 个，并对他们进行了详细的磁性表征，探究相同配体/不同端基配体、不同配体/相同端基配体体系中，配体与中心金属离子以及金属离子之间的相互作用对稀土配合物磁性的影响。.（2）后期工作对配合物的功能研究进行了拓展，进行了一些荧光材料方面的研究，以三种羧酸型配体合成了18种稀土MOF结构，并对其荧光性质进行表征，如配合物45在324nm处激发能够发射出暖白光，配合物52在305 nm处激发能够发射出白光。