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31.
基于不同位阻的三氰基构筑单元和双齿配体,合成了2个氰基桥联的Fe(Ⅲ)-Mn(Ⅱ)链状化合物。利用不同的结构扭曲类型调控了它们的磁性相互作用。化合物{[Fe(Ⅲ)(PzTp)(CN)3][Mn(Ⅱ)(5,5’-dmbpy)2]ClO4}n1;PzTp=tetrakis(pyrazolyl)borate;5,5’-dmbpy=5,5’-dimethyl-2,2’-bipyridine)显示为左右手螺旋链的一维2,2-CC链状结构并且表现出亚铁磁行为。化合物{[Fe(Ⅲ)(Tp*)(CN)3]2[Mn(Ⅱ)(dpqc)]·CH3OH·H2O}n2;Tp*=hydridotris(3,5-dimethylpyrazolyl)borate;dpqc=dipyrido[3,2-a:2’,3’-c]-(6,7,8,9-tetrahydro)phenazine)具有一维4,2-带状的双链结构并且表现出典型的反铁磁性相互作用。  相似文献   
32.
两个基于Mn席夫碱氰基桥联化合物的合成、结构和磁性   总被引:2,自引:2,他引:0  
本文利用MnⅢ席夫碱配合物作为前驱体,与含有氰根桥联配体的构筑基块K3[CoⅢ(CN)6]或Na[N(CN)2]反应合成了2个新的化合物[MnⅢ6(Salen)6(H2O)6.CoⅢ(CN)6][CoⅢ(CN)6].6H2O(1)和[MnⅢ(5-Br)Salen.N(CN)2].H2O(2),其中Salen为二-邻苯甲醛乙二胺。利用红外光谱、元素分析和X-射线单晶衍射分析对其结构进行了表征并测试了其磁学性质。结构分析表明化合物1由1个七核阳离子簇[Mn6Co]3+和一个平衡阴离子[Co(CN)6]3-组成的离子对化合物。而化合物2则为由MnⅢ组成的一维中性链结构,[N(CN)2]-利用叠氮桥联方式和金属离子配位。磁性研究表明,化合物1中[Co(CN)6]3-几乎不传递磁耦合作用,所以是一个顺磁体,但MnⅢ自身的零场分裂导致低χMT在低温时随温度下降而减小,而2则表现出弱的链内反铁磁性耦合作用。对比化合物1和2的磁性得知共轭体系[N(CN)2]-比同样是五原子配体[Co(CN)6]3-传递较强磁耦合作用。  相似文献   
33.
The cyano-bridged bimetallic complex [Nd(DMSO)2(H2O)2][Ni(CN)4]Cl with two-dimensional gridding molecule structure was synthesized and characterized. In the complex all four cyano groups of unit Ni(CN)42- are bound to Nd3+ ions. The crystal data for the title complex: monoclinic, space group P21/c, a=0.780 0(3) nm, b=1.509 7(6) nm, c=1.683 2(6) nm, β=115.231(14)°, Z=4, μ=4.311 mm-1, final R1=0.020 9, wR2=0.045 4. CCDC: 272214.  相似文献   
34.
1INTRODUCTION Recently,cyano-bridged lanthanide-transition me-tal complexes have been extensively investigateddue to their potential applications as precursors in the preparation of rare earth orthoferrites,fluores-cent and magnetic materials[1].Various complexes of this system have been obtained in order to ex-plore the relations between structures and pro-perties by using different ligands,such as DMF,4,4?-bipy,and so on,to fill the coordination sites of lanthanide ions[2~9].But up to…  相似文献   
35.
The title complex [La(betaine)2(H2O)6Fe(CN)6](2H2O (betaine = (CH3)3NCH2CO2) has been synthesized and characterized by X-ray single-crystal structure analysis. The crystal crystallizes in monoclinic, space group P21/n with a = 15.793(5), b = 8.927(3), c = 22.257(7) (A), β = 110.147(5)°, C16H38FeLaN8O12, Mr = 729.31, Z = 4, V = 2946.0(15) (A)3, Dc = 1.640 g/m3, μ(MoKα) = 1.988 mm-1, F(000) =1476, R = 0.0388 and wR = 0.0827 for 4237 observed reflections (I > 2σ(I)). The La3+ ion is nine-coordinated by one cyano nitrogen atom and eight oxygen atoms of two betaine and six water molecules. Each complex molecule is connected to form a 3D network structure by some O-H…O and O-H…N hydrogen bonds.  相似文献   
36.
我们利用具有不同对称性的同分异构体,通过改变分子间氢键网络,操控单链磁体行为,成功合成了2 例化合物:[Ni(L1)][Fe(Tp)(CN)3]2·3.5H2O (1)和[Ni(L2)][Fe(Tp)(CN)3]2·3H2O (2),其中Tp=hydrotris(pyrazolyl)borate,L1=3,4-bis(1H-imid-azol-1-yl)thiophen,L2=1,2-bis(1H-imidazol-1-yl)thiophen)。磁性研究表明,12表现为具有不同矫顽场的单链磁体行为。1的矫顽场为8.41 kOe,而2的矫顽场为3.84 kOe。  相似文献   
37.
Two new bimetallic cyano-bridged complexes [Ce(DMSO)4(H2O)3Fe(CN)6]·H2O 1 and [La(DMSO)4(H2O)3Co(CN)6]·H2O 2 have been prepared by the ball milling reaction method and structurally characterized by X-ray single-crystal structure analyses. Crystallographic data for 1:C14H32CeFeN6O8S4, Mr = 736.67, monoclinic, space group P21/n, a = 14.952(1), b =13.7276(9), c = 15.392(1) (A), β = 108.288(1)°, V = 2999.6(4) (A)3, Z = 4, Dc= 1.631 g/cm3,μ =2.304 mm-1, F(000) = 1480, R = 0.0593 and wR = 0.1611; and those for 2: C14H32CoLaN6O8S4,Mr=738.54, monoclinic, space group P21/n, a = 14.945(3), b = 13.731(3), c = 15.300(3) (A), β=107.806(1)°, V= 2989.3(11) (A)3, Z = 4, Dc = 1.641 g/cm3,μ = 2.288 mm-1, F(000) = 1480, R =0.0383 and wR = 0.1132. In both complexes the lanthanide ion is eight-coordinated in a square antiprism arrangement, and the Fe(Ⅲ) or Co(Ⅲ) ion in a nearly regular octahedral environment.The [LnM(CN)6(DMSO)4(H2O)3]·H2O (Ln = Ce and M = Fe for 1; Ln = La and M = Co for 2)species are held together via hydrogen bonds by coordinated water molecules, lattice water molecules and nitrogen atoms of cyanide groups to form a three-dimensional framework.  相似文献   
38.
基于不同位阻的三氰基构筑单元和双齿配体,合成了2个氰基桥联的Fe(Ⅲ)-Mn(Ⅱ)链状化合物。利用不同的结构扭曲类型调控了它们的磁性相互作用。化合物{[Fe(Ⅲ)(PzTp)(CN)3][Mn(Ⅱ)(5,5''-dmbpy)2]ClO4}n1;PzTp=tetrakis(pyrazolyl)borate;5,5''-dmbpy=5,5''-dimethyl-2,2''-bipyridine)显示为左右手螺旋链的一维2,2-CC链状结构并且表现出亚铁磁行为。化合物{[Fe(Ⅲ)(Tp*)(CN)3]2[Mn(Ⅱ)(dpqc)]·CH3OH·H2O}n2;Tp*=hydridotris(3,5-dimethylpyrazolyl)borate;dpqc=dipyrido[3,2-a:2'',3''-c]-(6,7,8,9-tetrahydro)phenazine)具有一维4,2-带状的双链结构并且表现出典型的反铁磁性相互作用。  相似文献   
39.
1 INTRODUCTION In the last decade, cyano-bridged Prussian Blueanalogues[1] have been intensively studied from theviewpoint of application as functionalized molecule-based magnets[2], chemical sensor materials[3], fluo-rescent materials[4] and zeolitic-type materials[5, , 6]etc. In 1976, a series of cyano-bridged three-dimen-sional rare earth hexacyanometalates(IIILnM(CN)6?nH2O (M = Fe or Cr, n = 4 or 5) were crystallized andsubjected to single-crystal X-ray analysis[7]. …  相似文献   
40.
A new lanthanumⅢ-ironⅢ complex [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4]·H2O 1 (DMSO=dimethylsulfoxide) has been prepared by a facile approach, ball-milling method, and characterized by X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a=9.7125(3), b=21.5336(7), c=14.3804(5) (A), β=93.242(3)°, C16H34FeLaN6O7S5, Mr=777.55, V=3002.8(2)(A)3, Z=4, Dc=1.720 g/cm3, S=1.053, μ(MoKα)=2.278 mm-1, F(000)=1564, R=0.0490 and wR=0.1270. The crystal structure analysis of 1 reveals a slightly distorted squareantiprism eightfold-coordinated La(Ⅲ) ion and a 1-D zigzag chain structure extending through the Fe-CN-La-NC-Fe linkages. The [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4] species are held together via hydrogen bonds to form a three-dimensional framework.  相似文献   
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