氰根桥连3d金属簇合物的合成、结构及磁学性质研究

SYNTHESIS, STRUCTURES AND MAGNETIC PROPERTIES OF CYANIDE BRIDGED 3d METAL CLUSTERS

程玥

11849184

硕士

化学

张元竹

2020-05-30

2020-07-08

哈尔滨工业大学

深圳

随着信息化时代的发展，人们对高密度信息存储的需求愈发强烈。与传统无机磁性材料相比，分子基磁体在尺寸上表现了独特的优越性，具有潜在的应用前景。其中，氰根桥连金属簇合物因在分子磁领域表现出许多有趣的磁学功能而备受关注。氰根作为目前最短的双原子桥连配体，能够很好的传递磁电相互作用。氰根的线性配位模式为含氰根配合物的模块化可控合成提供了可能性，通过引入不同的顺磁金属中心和配体，可以达到调控这类化合物的结构和磁学性质的目的。本论文使用了一系列广泛使用的三氰合铁构筑基元和不同构型的3d金属，合成出了数例零维、一维氰根桥连金属化合物，并对他们的单晶结构和磁学性质进行了表征，主要内容如下：使用不同位阻的三氰构筑基元，引入四面体的钴离子，得到了四个新颖的零维氰根桥连铁钴簇合物：{Co2Cl2(DMF)4[(Tp4-Me)Fe(CN)3]2} (1, Tp4-Me = 一氢三（4-甲基吡唑基）硼酸根)、(H3O+)@{Co4Cl4[(Tp4-Me)Fe(CN)3]4} (2)、(MePh3P)4{Co6Cl6[(Tp4-Me)Fe(CN)3]6}·15CH3CN·3CH3OH·2H2O (3)、(BnEt3N)4{Co5Cl8[(Tp*)Fe(CN)3]4}·4CH3CN·2H2O (4, Tp* = 一氢三（3,5-二甲基吡唑基）硼酸根)。其中，六棱柱构型的3和双三角双锥构型的4为氰根桥连金属簇合物提供了两种新的分子骨架。化合物1在零场下表现出单分子磁体行为，其有效能垒为30.7K。使用同一种三氰构筑基元，将杂多酸作为大的抗衡阴离子引入体系中，采用不同的合成策略得到了三例杂多酸-铁钴簇合物的复合结构：[Co(DMF)3]6[(pzTp)Fe(CN)3]6(HPMo12O40)3 (5, pzTp = 四吡唑基硼酸根)，[Co(TpEtOH)]4[(pzTp)Fe(CN)3]4(HPMo12O40)2·nDMF (6, TpEtOH = 2,2,2-三吡唑基乙醇)以及[{Co(CH3OH)4}{Co(CH3OH)3}2{(pzTp)Fe(CN)3}3][PMo12O40]·-11.5CH3OH·H2O (7)。他们的成功合成显示出了多酸阴离子可以对氰根簇合物结构进行有效调控。同时也为引入多酸自身功能（催化，发光），从而合成单晶型多功能复合材料提供可能性。最后，分别通过引入四配位的钴离子和大的抗衡阴离子，得到了两例一维珍珠链形氰根桥连金属化合物：Co(DMF)4{(CoCl2)2[(Tp4-Me)Fe(CN)3]2} (8)和{[(Tp*)Fe(CN)3]2Ni2(DMF)8}{[(Tp*)Fe(CN)3]2Ni3(DMF)10(H2O)2}(PMo12O40)2 (9)。化合物8和9都表现出单链磁体行为。

With the development of information age, the demand for high-density information storage is becoming stronger. Compared with the traditional inorganic magnetic material, the molecule-based magnets show unique superiority in size. Cyanide bridged metal cluster has attracted more and more attention because it shows a number of exciting magnetic functionalitics in the field of molecular magnetism. As the shortest diatomic bridging ligand, cyanide can propagate magnetic interactions. Characteristic linear coordination mode of cyanide provides the possibility for the modular and controllable synthesis of cyanometallates. By introducing different paramagnetic metal centers and ligands, the regulations of the structure and magnetic property of the compounds can be achieved. In this thesis, several novel zero-dimensional and one-dimensional cyanide-bridged metal compounds have been synthesized by the complexation of a series of widely used tricyanoiron building units together with 3d metal centers with different configurations. Their structures and magnetic properties were characterized:Four novel zero-dimensional cyanide bridged Fe-Co clusters were synthesized by using different tricyanoiron building units and tetrahedral coordination cobalt, formulated as {Co2Cl2(DMF)4[(Tp4-Me)Fe(CN)3]2} (1, Tp4-Me = hydridotris(4-methylpyrazol-1-yl)borate), (H3O+)@{Co4Cl4[(Tp4-Me)Fe(CN)3]4} (2), (MePh3P)4{Co6Cl6[(Tp4-Me)Fe(CN)3]6}·15CH3CN·3CH3OH·2H2O (3) and (BnEt3N)4{Co5Cl8-[(Tp*)Fe(CN)3]4}·4CH3CN·2H2O (4, Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate). Notably, the hexagonal prism-shaped cluster 3 and the bis(trigonal bipyramidal) cluster 4 provide two novel molecular skeletons in the cyanometallate family. Furthermore, compund 1 behaved as a single molecule magnet under zero field with the effective energy barrier of 30.7 K.By introducing the polyoxometalates as large counterions into the synthesis of cyanide-bridges cluster, three hybrid compounds of cyanometalates and polyoxometalates were synthesized. They are [Co(DMF)3]6[(pzTp)Fe(CN)3]6-(HPMo12O40)3 (5, pzTp = tetrapyrazolylborate)，[Co(TpEtOH)]4[(pzTp)Fe(CN)3]4-(HPMo12O40)2·nDMF (6, TpEtOH = 2,2,2-tris-(pyrazolyl)ethanol) and [{Co(CH3OH)4}{Co(CH3OH)3}2{(pzTp)Fe(CN)3}3][PMo12O40]·11.5CH3OH·H2O (7). Their successful synthesis showed that polyoxometalate anions can effectively regulate the structure of cyanide clusters. At the same time, it also provides the possibility of introducing polyoxometalate's own functions (such as catalysis, luminescence) to synthesize single-crystal multifunctional composite materials.Two one-dimensional pearl chain cyanide bridged metal clusters were synthesized by introducing cobalt ions with tetrahedral coordination and large counterions respectively. They are Co(DMF)4{(CoCl2)2[(Tp4-Me)Fe(CN)3]2} (8) and {[(Tp*)Fe(CN)3]2Ni2(DMF)8}{[(Tp*)Fe(CN)3]2Ni3(DMF)10(H2O)2}(PMo12O40)2 (9). Compound 8 and 9 behaved as single chain magnets.

分子磁性材料 氰根桥连 簇合物 单分子磁体 单链磁体

molecular magnetic materials cyanide bridged cluster compound single-molecular magnet single-chain magnet

中文

联合培养

南方科技大学

程玥. 氰根桥连3d金属簇合物的合成、结构及磁学性质研究[D]. 深圳. 哈尔滨工业大学,2020.