【作者】 岳衍峰；

【导师】 高恩庆；

【作者基本信息】 曲阜师范大学 ， 无机化学， 2004， 硕士

【摘要】 随着配位化学研究的发展，配位聚合物的结构和磁性日益受到人们的关注。为了合成新颖的聚合结构、发现新的磁现象和磁相互作用机理，探讨分子体系的磁性和结构相关性，本文以叠氮离子（N₃^-）作为传递磁交换的主要途径，利用其丰富的桥联方式和磁性传递特性，辅之以具有特定配位形式的有机辅助配体，构筑了具有特定结构和磁性的过渡金属离子配位聚合物，共获得了14个一维、二维及三维配位聚合物（含三个分子基磁体），并进行了单晶结构测定和磁性表征。 本论文共分两个研究部分。第一部分主要论述了含双齿辅助配体的叠氮桥配位聚合物的结构和磁性，第二部分则讨论了含开链二嗪桥及叠氮桥的配位聚合物的结构和磁性。 一、含双齿辅助配体的叠氮桥配位聚合物的结构和磁性 （1）三个一维叠氮桥Mn（Ⅱ）配位聚合物（1-3）：以双齿席夫碱配体为辅助配体合成了三个一维叠氮桥Mn（Ⅱ）配位聚合物。Mn（Ⅱ）离子间由双EO叠氮桥和双EE叠氮桥交替桥联形成一维链状结构。磁性分析表明，链内存在交替的铁磁-反铁磁相互作用，以反铁磁相互作用为主。结合文献数据，对该类配合物的磁-构相关性作了一定的总结。 （2）两个一维叠氮桥Cu（Ⅱ）配合物（4，5）：化合物4，5均为含单EO叠氮桥的均一螺旋链，磁性分析表明：配合物4链内相邻金属离子间为反铁磁相互作用；配合物5链内相邻金属离子间为铁磁相互作用，链间为反铁磁相互作用。二者在磁性质的差异是由Cu（Ⅱ）的配位环境和桥联参数等因素不同导致的。 （3）一个二维叠氮桥Mn（Ⅱ）配合物（6）：配合物6的二维（6，3）层状结构是由单EE叠氮桥连接双核单元形成的，双核单元又由双EO叠氮桥联两个Mn（Ⅱ）离子构成。磁性分析表明配合物6的二维层内单EE叠氮桥和双EO叠氮桥分别传递反铁磁和铁磁相互作用，但整体表现反铁磁相互作用。由于二维层内Mn（Ⅱ）离子间的不对称交换作用，导致了层内自旋倾斜现象的曲阜师范大学硕士研究生毕业（学位）论文中文摘要发生，因而6具有弱铁磁性。结合文献数据，对具有二维（6，3）层状结构叠氮桥Mn（II）配合物的磁一构相关性作了一定的总结，并探讨了在该体系内导致自旋倾斜的原因。二、含开链二嗦桥及叠氮桥的配位聚合物的结构和磁性（1）两个一维手性叠氮桥Mn（11）配合物（7、8）及一个二维Mn（11）配合物（9）: 本文将具有潜在手性源的双（二齿）开链二嗦类配体引入叠氮体系，通过自 发拆分过程得到了两个一维手性分子基磁体。化合物7和8是由具有不 同分子拓扑结构的手性双核或三核单元构成的均手性一维链，构筑单元 的手性是由双（二齿）配体与两个金属离子配位发生扭曲导致的。在化合物 7中含有等腰三角形[Mn3（L6）2困3)z]手性单元，而在化合物8中含有双螺 旋单元仁MnZ(L从]。配合物7和8的手性单元间均由EE叠氮桥相互连接， 单EE叠氮桥倾向于以不对称的方式连接金属离子，并且呈现出多变的扭 曲角（M一N一N一N一M），促成了手性单元之间的手性传递。配体L6和L7分别 含有一个和两个可作为氢键给体的氨基，同时叠氮离子上未配位氮原子 可作为氢键受体，通过链间的氢键作用使得相邻链具有相同的手性，从 而诱发自发拆分。利用没有取代基的LS配体则得到非手性晶体9，虽然 化合物9也含有手性双核基元，但连接手性双核基元的双EO叠氮桥间存 在对称中心，导致配合物手性消失。化合物7是一个由同金属亚铁磁链 构成的变磁体，其反铁磁有序温度和临界场分别是2.9K和1.1 kG。其中 亚铁磁的净自旋是由特定“稠合三角形”结构内Mn（ll）离子间交替的铁 磁一反铁磁相互作用产生的。化合物8是一个反铁磁体，在一维内通过双 二臻桥和单EE叠氮桥联的Mll（II）离子间均为反铁磁相互作用。化合物9 是一个由自旋倾斜引起的弱铁磁体，在10.1和14.6K温度下，分别有一 个磁相变过程。（2）五个高维叠氮桥cd（II）配合物（10一14）:化合物10、n为不同桥联方式的 二维（6，3）层状结构，而12一14具有相同的三维（10，3）聚合网络结构。更多还原

【Abstract】 In the field of coordination chemistry, the design and magnetic properties of polynuclear molecules and especially clusters of high nuclearility and coordination polymers currently attract considerable interest. In order to design supermolecular architectures and reveal the fundamental mechanism of magnetic interaction and the megneto-structural correlation, we selected transition metal ions and organic co-ligands containing special coordination information as the object of our study. Meanwhile we chose sodium azide as the bridging ligand, which is an intriguing synthetic approach to molecular-based magnets due to the remarkable diversities of sodium azide in structural and magnetic behaviors. In this thesis, 14 compounds have been synthesized and characterized by elemental analyses, IR, X-ray analyses, variable-temperature and variable-field magnetic measurements.This thesis contains two main parts: (1) the structures and magnetic properties of azido -bridged complexes with bidentate Shiff-base ligands, and (2) the structures and magnetic properties of azido-bridged complexes with bi(bidentate) diazine ligands.1. The structures and magnetic properties of azido-bridged complexes with bidentate Shiff-base ligands(i) Three 1D Mn (II) -azido coordination polymers (1-3). In the three Mn(II) complexes, Mn(II) ions are alternately bridged by two end-to-end (EE) and two end-on (EO) azido ligands. Magnetic analyses have revealed the existence of alternating ferromagnetic and antiferromagnetic interactions through the EO and EE azido bridges, respectively. In order to deduce some information about magnetostructural correlation, the structural and magnetic data have been investigated.(ii) Two 1D Cu(II)-azido coordination polymers (4, 5). Two complexes with onlysingle EO azido bridges, exhibiting antiferromagnetic and ferromagnetic interactions between neighboring metal ions, respectively.(iii)One 2D Mn(II)-azido coordination polymers (6). Compound 6 is a sheet of dimmers, in which two Mn(II) ions are bridged by two EO azides and the dimers are linked by the single EE bridges into a sheet. Magnetic studies on the complex reveal that ferromagnetic and antiferromagnetic interactions are mediated through the EO and EE azido bridges, respectively. The complex exhibits spin canting related to the lack of inversion centers between the EE azido bridged Mn(II) ions, but long-range ordering of the residual spins is not achieved.2. The structures and magnetic properties of azido-bridged complexes with bi(bidentate) diazine ligands(i) Two 1D Chiral Mn(II) and one 2D Mn(II)-azido coordination polymers (7-9). By incorporating an achiral diazine ligand, which can be locked in a chiral conformation upon coordination, into the Mn(II)- azido system, two ID chiral chain is induced. The process is called spontaneous resolution. The 2D layers are consisted of Mn(II) tetranuclear units, which are centrosymmetric. Compound 7 represents a new example of the rare phenomenon of homometallic ferrimagnetism, and behaves as a metamagnet built of ferrimagnetic chains, the critical temperature of antiferromagnetic ordering and the critical field of the antiferro-to-ferromagnetic transition being TN = 2.9 K and Hc = 1.1 kG, respectively. The noncompensation in spin moment is achieved by a specific alternation of ferro- and antiferromagnetic interactions within the unusual "fused triangles" chain. Compound 8 is a ID antiferromagnet with antiferromagnetic interactions mediated by the double diazine and the single EE azido bridges. Compound 9 exhibits weak ferromagnetism due to spin canting, while it undergoes two magnetic transitions at about 10.1 and 14.6 K, respectively.(ii) Five Cd(II)-azido coordination polymers (10-14). The various arrangements of azido ions give two 2D polymeric sheets of complexes 10, 11 and three 3D networks of 3, 4, and 5. Meanwhile the interesting structures of the five azido-bridged complexes containing a series of bi(bidentate) diazine ligands indicate the varieties of azido ions in designing polymeric archi更多还原