刺激-响应型可逆转变单分子磁体的构筑及其磁-构关系研究

Single-molecular magnets (SMMs) have been of great interest in the field of molecular magnetic bistable materials because of their applications in high density data storage, quantum computing, spintronics. SMMs have been already studied fruitfully, but the number of reversible switchable SMMs have been studied very limitedly, and their chemical reactivities and stimuli-responsive abilities also have been rarely studied. This project will be focused on the research frontiers of the molecular magnetic bistable materials. Guided by the functional groups, the reversible switchable SMMs containing structure and properties transformation will be achieved through the appropriate solvent and light conditions. It will be selected with excellent properties of stimuli-responsive arrays of reversible switchable SMMs. In this regard, we can design and synthesis the solvent-and light-responsive reversible switchable SMMs based on the triazinyl and spiropyran ligand, respectively. Furthermore, we will investigate in detail and study intensely their magnetic relaxation behavior and dynamic reversible switching laws under the solvent-and light-responsive conditions. Based on this project, we will promisingly lay a foundation for the design and preparation of new multifunctional molecular magnetic materials such as solvent-and light-responsive magnetic switch machines.

由于其在高密度信息存储、量子计算机和自旋电子学等领域具有重要的潜在应用价值，单分子磁体成为分子磁性双稳态材料的重要研究领域之一。然而，目前单分子磁体存在动态可逆转变研究较少，反应活性或刺激-响应性后续研究不够的问题。本项目立足于分子磁性双稳态材料研究前沿，以功能化基团为导向，通过合适的溶剂变换和光激发条件，实现单分子磁体体系的结构和性质的可逆动态转变，从而筛选出具有刺激-响应型可逆转变单分子磁体。据此，以三嗪多齿螯合配体可以设计合成溶剂-响应型单分子磁体，以螺吡喃基配体设计可以合成光激发-响应型单分子磁体。并深入研究在溶剂、光学活性等刺激下体系的慢磁弛豫行为和动态可逆转变规律。本项目的实施，有望为设计合成新型溶剂-响应和光-响应磁开关等多功能分子材料奠定了基础。

单分子磁体是分子双稳态材料研究的重要领域之一，因此，合理设计和调控条件是获得优异性能单分子磁体的重要课题。本项目围绕微扰条件下的单分子磁体研究开展研究，通过金属中心变换、配体设计、阴离子和溶剂调控、维度切换、磁各向异性调控等方面，实现了单分子磁体结构和性质的调控。设计合成了不对称四齿螯合配体，构筑了具有七配位的Co(II)和八配位的Fe(II)单离子磁体。利用特殊的两齿螯合配体，通过阴离子调控，合成了具有慢磁弛豫行为的四配位和七配位钴化合物。利用苯并咪唑-双羧酸策略，通过变换羧酸，获得了不同维度的钴基磁性配合物；通过变换苯并咪唑取代基基团，获得了一系列二维三角格子的钴基配位聚合物。利用席夫碱的3d-4f金属构筑块，引入三原子离子叠氮离子，获得了具有四核的3d-4f单分子磁体；通过引入长的桥连配体二氰胺根离子，获得了具有二维结构的3d-4f单分子磁体。通过对配体场的设计和分子对称性考虑，获得了具有不同对称性的零维和一维的4f单离子磁体。利用基于六氟乙酰丙酮配体的钴配合物，实现了易面磁各向异性向易轴磁各向异性转变。设计合成了一系列具有三唑基团的五齿螯合配体，实现了溶剂诱导下具有七配位五角双锥结构的钴单离子磁体和栅格状四核磁性配合物的调控。到目前为止，已经发表Dalton Trans., Chem. Asian J., CrystEngComm等SCI期刊论文9篇，申请发明专利1项。