【作者】 刘亚冰；

【导师】 徐吉庆；

【作者基本信息】 吉林大学 ， 应用化学， 2007， 博士

【摘要】 本论文主要研究非经典金属-氧簇合物的合成、结构与性能,旨在合成出具有新颖结构的金属-氧簇合物及簇聚物,并在合成研究的基础上,初步探讨特殊结构化合物的合成条件、有机配体对产物结构的影响、簇合物的热稳定性和磁学性能。1.首次合成了六个非经典的Keggin型钨-钒氧簇合物及其簇聚物[第三章]。其中化合物1和2分别为以四帽或二帽Keggin型钨-钒氧阴离子为建筑块,[Cu（en）₂]²⁺为桥连基团构成的二维层状结构;化合物3是由二帽Keggin型簇阴离子通过无序的端氧连成的一维链;化合物4是首例二帽Keggin型簇阴离子以共价键支撑过渡金属配合物阳离子的结构;化合物5和6是同构的,均由二帽Keggin型簇阴离子和[Fe（phen）₃]²⁺阳离子组成的具有分立结构的簇合物。2.合成了十个非经典的Keggin型钼-钒氧簇合物及其簇聚物[第四章]。其中化合物13和14为首次合成的以二聚体为建筑块,连接而成的一维链状结构;化合物7为基于二帽Keggin型簇单元所构成的具有三维结构的簇聚物;化合物8,9,11,12,15具有相同的结构,是以不同的双支撑的四帽Keggin型簇阴离子为结构单元,以[M（en）₂]²⁺为桥连基团构成的一维链状结构;而化合物10和16则为具有分立结构的相似簇合物。3.合成了两个非经典的钒-氧簇聚物[第五章]。其中化合物17是以经典的[V₁₈O₄₂]^6-为基本结构单元,以[Ni（en）₂]_<sup>2+为桥连基团形成的扩展结构;化合物18则是基于少见的[V₁₀O₂₅]^4-簇的扩展结构化合物。4.对所合成的化合物进行了元素分析、红外光谱、光电子能谱、顺磁共振、X-射线粉末衍射等表征,对部分化合物进行了热稳定性和磁学性能的研究。论文还详细分析并阐述了上述化合物的合成条件和方法,有机配体的各种变化对产物结构的影响,为该体系的进一步研究奠定了基础。更多还原

【Abstract】 Polyoxometalates (POMs) represent a fascinating class of inorganic chemistry with a structural variety and interesting properties, which are of use in fields as diverse as catalysis, sorption, molecular electronics, medicine, etc. As the applications of hydrothermal technique on the syntheses, various organic-inorganic hybrid materials of particular properties emerges constantly and much attention has been caused on the performances studies of various materials. In this field, an important advance is to decorate well-known polyoxoanions with various organic and/or transition metal complex moieties and then to link them up into one-, two-, even three-dimensional extended solid materials in appropriate ways. The introduction of metal complex can not only enrich the frameworks of polyoxometalates but also ameliorate their electronic and mangnetic properties. Based on this mechanism, we synthesized some non-classical metal-oxygen clusters, the cluster-polymers based on tungsten-vanadium and molybdenum-vanadium oxygen clusters. On the bases of X-ray structural analyses, some central compounds have been characterized by IR, XPS, EPR, XRD spectra. The thermal analyses and magnetic properties of some compounds have been studied, which would take an important role in the explorations of structures and functions for the compounds.I non-classical tungsten-vanadium oxygen clustersApplying in hydrothermal synthesis reactions, we synthesized six non-classical tungsten-vanadium oxygen clusters. [Cu(en)2]2[CuWVI5WV4VIV7O44{Cu(en)2 (H2O)}2]·4H2O 1, [Cu(en)2(H2O)] [Cu0.5(en)]3[CuWVI9WVVIV4O42{Cu(en)2}]·3H2O 2, (H2en)2(H3O)7[WVI6VVVIV8O42]·2H2O 3, [Zn(en)2(H2O)]3[WVI5WV5VVVIV4O42 {Zn(en)2}] 4, [Fe(phen)3]2[WVI8.5WV2VVVVI3.5O42]·3H2O 5, [Fe(phen)3]2 [WVI10VVI5O42]·6H2O 6. Compound 1 is composed of the [CuWVI5WV4VIV7O44 {Cu(en)2(H2O)}2]4-, which is further linked into a novel 2D layer through four [Cu(en)2]2+ fragments. The sturucture of compound 2 features a novel 2D layer built from the bicapped Keggin [CuWVI9WVVIV4O42]7- anions are decorated with [Cu(en)2]2+ unit, which is further interconnected by three [Cu(en)2]2+ groups via the terminal oxygen atoms and double- bridge atoms of clusters. In the crystal structure of 3, the reduced bicapped Keggin [WVI6VVVIV8O42]11- units having a high V/W ratio are connected by (μ2-O)2 oxygen atoms forming 1D chains. Compound 4 represents the first example that an unusual reducted bicapped Keggin [WVI5WV5VVVIV4O42]8- cluster is covalently bonded to a [Zn(en)2]2+ unit via the surface bibridged oxygen atoms. The polyoxoanions of Compounds 5 and 6 are decorated with [Fe(phen)3]2+ cations, and both of them have analogous structure to each other with slightly different packing modes of polyoxoanions, [Fe(phen)3]2+ cations and water molecules. They are further linked to from 2D supramolecular networks through hydrogen bonging. The X-ray single crystal analysis, elemental analysis, IR, XPS, EPR, XRD and TG etc., have been performed on these compounds. Variable-temperature magnetic susceptibility measurements of compound 1, 2 and 3 reveal the feature of antiferromagnetic exchange.II non-classical molybdenum-vanadium oxygen clustersApplying in hydrothermal synthesis reactions, we synthesized ten non-classical tungsten-vanadium oxygen clusters. H3{[MoVI8VIV6O36(PO4)][Cu(en)2]4}(MoO4)·4H2O 7, [Cu(en)2]{[Cu(en)2]2[MoVI5MoV3VIV8O40(PO4)]}·4H2O 8, [Co(en)2] {[Co(en)2]2[HMoVI4MoV4VIV8O40(PO4)]}·5H2O 9, [Co(en)3]2[H3PMoVI8VIV6O42]·H2O 10, [Ni(en)2]{[Ni(en)2]2[MoVI5MoV3VIV8O40(VO4)]}·2H2O 11, [Ni(en)2] {[Ni(en)2]2[MoVI5MoV3VIV8O40(VO4)] }(dien)·H2O 12, [{[Cu(en)2][Cu(en)2(H2O)] [SiMoVI8VIV6O42]}2{[Cu(en)2]0.5}][Cu(en)2][Cu(en)2(H2O)]·H2O 13, (H2en)2 (H3O)12[SiMoVI14MoV2VV2VIV10O84] 14, [Ni(en)2]{[Ni(en)2]2[MoVI6MoV2VIV8O40 (SiO4)]}(dien)·2H2O 15, [Co(en)3]2[SiMoVI8VV4VIV2O42]·6H2O 16. These compounds can be grouped into three systems. The compounds 7-10 belonging to the P/Mo/V/ O system have been synthesized. Compound 7, which has 3D network structure, is based on the molybdenum-vanadium cluster of bicapped Keggin structure linked by the transition metal complex ion [Cu(en)2]2+ bridges. The isomorphic compounds 8 and 9 feature a 1D chain built from the reduced tetra-capped pseudo-keggin polyoxoanion, which is further interconnected by [M(en)2]2+ (M = Cu, Co) groups via the terminal oxygen atoms of polyoxoanions. Compound 8 and 9 represent the first 1D chain constructed from the reduced P/Mo/V/O tetra-capped Keggin polyoxoanions and [M(en)2]2+ (M = Cu, Co) cations. Compound 10 is a discrete cluster compound with bicapped Keggin structure P/Mo/V/O cluster, and [Co(en)2]2+ complex ion act as the balanced cations. The compounds 11-12 belonging to the Mo/V/O system have been synthesized. Compound 11 belongs to the polymer of cluster with 1D chain structure based on tetra-capped Keggin cluster units linked through the bridged [Ni(en)2]2+ groups. The compound 12 is isomorphic with 11, and the differences between compound 11 and 12 are having dien in 12 and the amount of lattic water molecules. The compounds 13-16 belonging to the Si/Mo/V/O system have been synthesized. Compound 13 exhibits a unique 1D organic-inorganic hybrid chain containing double-supporting bi-capped Keggin polyoxoanion dimer linked by transition metal coordination fragments. Compound 14 is also possessed of 1D structure based on dimerized bi-capped Keggin cluster consisting of two kinds of polyoxoanion units having different valence states, [Si(1)MoVI6MoV2VIV6O42]10- and [Si(2)MoVI8VV2VIV4O42]6-, and linked by two terminal oxygen atoms from two dimerized cluster units. These two compounds represent the first 1D derivatives based on dimerized bi-capped Keggin-type polyoxoanion in the Mo/V/Si/O system under hydrothermal condition. Compound 15 is isomorphic with compound 8, except that Cu, P atoms are replaced by Ni and Si atoms, respectively. Charge distribution of Mo atoms in polyoxoanion of 15 is different from that in 8 and these result in somewhat different corresponding bond distance in 15 and 8. Compound 16 is a discrete cluster compound with bicapped Keggin structure Si/Mo/V/O cluster, and [Co(en)2]2+ complex ion act as the balanced cations. The X-ray single crystal analysis, elemental analysis, IR, XPS, EPR, XRD and TG etc., have been performed on these compounds. The magnetic behavior of compounds 8, 11 and 13 were measured, and these data between 50 K and 250 K is coincident with the Curie-Weiss law, the Weiss Constant is small than zero, which indicates the presence of antiferromagnetic interaction between the metal ions of them. Unfortunately, it is too difficult to fit the experimental mangentic data of these hetero-polymetallic spin systems using a suitable theoretical model.III non-classical vanadium oxygen clustersApplying in hydrothermal synthesis reactions, we synthesized two non-classical vanadium oxygen clusters. [Ni(en)2]3[VV7VIV11O42CI]·8H2O 17 and [Cu(en)2]2 [VV6VIV4O25] 18. Compound 17 exhibits an interesting 3D supramolecular framework assembled by sinusoidal-like arrangement of 2D coordination polymer layers and cryatal water molecules. Compound 18 features a 3D network built from 2D inorganic layer-like structure interconnected via [Cu(en)2]2+ units. The X-ray single crystal analysis, elemental analysis, IR, XPS, EPR and TG etc., have been performed on both compounds. The magnetic behavior of compound 17 was measured, and the data indicates the existence of stronger antiferromagnetic coupling of eleven V(IV) and three Ni(II) ions.更多还原