稀土磁弛豫体系的控制合成、多功能化和磁性调控是当前分子磁性领域的研究热点。本论文通过引入金属卤化物功能单元，通过使用光响应有机配体，运用结构基元或超分子化学的方法构筑了26例结构多样的稀土配合物，实现了磁弛豫、半导体和非线性光学性质的共存，实现了光响应稀土磁弛豫体系的构筑以及光对磁弛豫行为的调控；通过磁稀释和理论计算相结合的方法，深入研究了磁弛豫体系中镝离子间的磁耦合对磁学行为的调节作用。主要的研究成果如下：

1. 将铋金属卤化物单元引入到稀土磁弛豫体系，构筑了9例具有半导体性质的稀土单离子磁体，并通过改变卤素离子和溶剂分子实现了磁弛豫、半导体和非线性光学性质的共存。结构-性质关系研究表明，所有配合物的磁弛豫行为来源于稀土离子的磁各向异性；卤化铋阴离子赋予了配合物半导体属性；溶剂分子的定向排列和畸变的溴化铋阴离子是配合物倍频效应的重要来源。

2. 合成了具有光响应行为的联吡啶鎓衍生物配体，并与镝离子构筑了9例具有磁弛豫行为的稀土配合物。通过增加光响应配体上羧基的数目，实现了配合物从双核到一维或二维的结构调控。通过更换电子给体的种类，改善了配合物的光响应行为，并进一步探讨了配合物中电子给体和受体基团的堆积方式与光响应行为之间的关系。通过溶剂分子诱导的结构相变，首次在联吡啶鎓体系实现了光响应行为对量子隧穿和热弛豫行为的调节。

3. 使用铜-席夫碱结构基元与稀土离子和氮氧联吡啶反应，合成了4例具有磁弛豫行为的层状异金属配合物，探讨了同一配位场对不同稀土离子磁各向异性和磁弛豫行为的影响。

4. 合成了基于氮氧吡啶羧酸配体和双核基元的纯钇和镝掺杂的层状配合物。磁性研究表明镝掺杂配合物在零场下表现出慢磁弛豫行为。通过与纯镝配合物磁学数据的对比，结合理论计算研究发现，配合物双核内的铁磁和反铁磁相互作用分别会抑制和增强量子隧穿行为，从而增强或湮灭镝离子的热弛豫行为，体现了羧酸基团位置的变化对镝离子间连接模式和磁相互作用，以及配合物磁弛豫行为的调节作用。

The controlled synthesis, multi-functionalization and magnetic property regulation of lanthanide systems with slow magnetic relaxation are the hotspots in the field of molecular magnetism. In this paper, twenty-six lanthanide complexes featuring various crystal structures were successfully constructed by combing different metal halide units, employing photo-responsive organic ligands and/or utilizing building-block or supramolecular approaches. Thus, the coexistence of magnetic relaxation, semi-conductivity and nonlinear optical properties in lanthanide system was successfully achieved. The rational construction of lanthanide magnetic dynamic systems with photo-responsive behavior and the regulation of photo-response behavior on magnetic relaxation were realized. In addition, by employing magnetic dilution approach and theoretical calculation, the influence of magnetic interaction on magnetic relaxation behavior was deeply investigated. The main achievements are as follows:

1. Nine lanthanide complexes with semi-conductivity were constructed by introducing bismuth metal halide unit into lanthanide magnetic dynamic system. The coexistence of magnetic relaxation, semi-conductivity and nonlinear optical properties was realized by employing different halide ions and solvent molecules. The physical property-structural relationship study indicates that the magnetic relaxation behavior originated from strong magnetic anisotropy of lanthanide ions, the semi-conductivity properties derived from bismuth halide anions, and the orientation of solvent molecules together with the distorted bismuth bromide anions led to the second harmonic generation effect.

2. Nine dysprosium complexes featuring magnetic relaxation were obtained by using bipyridinium derivative with photo-responsive behavior.By increasing the number of carboxylic groups on organic ligands, the modulation of structures from binuclear to chains or layers was achieved. And the photo-response behaviors of the complexes were improved by varying the species of electron donors. Furthermore, the relationship between photo-response behavior and the packing of photo-response donor and acceptor in the complexes was discussed. Through the solvent-induced structural transition, the regulation of quantum tunneling and thermal-activated relaxation process by photo-responsive behavior in bipyridinium-containing system was realized for the first time.

3. Four layered heterometallic complexes with slow magnetic relaxation behavior were synthesized by the reaction of lanthanide ions and bipyridine-N-oxide with copper Schiff-based motifs. And, the influence of the same ligand field on the magnetic anisotropy of different lanthanide ions together with the dynamic magnetic behavior was also investigated.

4. Two-dimensional yttrium and dysprosium-doped complexes were synthesized by reacting pyridine-N-oxide carboxylate with binuclear building-blocks. Magnetic studies showed that the dysprosium-doped complexes exhibited slow magnetic relaxation under zero field. Magnetic dilution studies together with the theoretical calculation suggested that the ferromagnetic or antiferromagnetic interactions within dimeric units could suppress and enhance the quantum tunneling behavior, respectively, and thus promote or quench the thermal-activated process of dysprosium ions, displaying the tuning effect of the position change of the carboxylic acid group on the magnetic interaction between dysprosium ions as well as the overall dynamic magnetic behavior.