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通过三缺位Keggin结构杂多阴离子[α-A-PW9O34]9-和二氯甲基苯基硅烷在乙腈溶液中反应,合成了一例结构新颖的甲基苯基硅衍生物[(C4H9)4N]3[α-A-PW9O34(C6H5SiCH3)3](1),并对其进行元素分析,红外光谱,紫外光谱,热分析和X-射线单晶衍射等表征。该配合物属于三方晶系,空间群为R3m,晶胞参数:a=2.261 3(2)nm,b=2.261 3(2)nm,c=1.797 6(4)nm,V=7.960 2(18)nm3,Z=3。在配合物中,阴离子[α-A-PW9O34(C6H5SiCH3)3]3-呈C3v对称,3个甲基苯基硅基团连接在三缺位的阴离子[α-A-PW9O34]9-表面,整个阴离子显示"开放结构"。 相似文献
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稀土Dy3+掺杂Fe3O4的合成及电磁性质 总被引:4,自引:0,他引:4
通过溶胶-凝胶法,合成了稀土Dy^3+掺杂的Fe3O4样品,研究了掺杂对电磁性质的影响。通过X射线衍射分析发现,由于离子半径的不匹配,Fe3O4中稀土离子的高浓度掺杂不能实现,仅有极少量的稀土离子取代了Fe3O4中的Fe^3+。通过振动样品磁强计对磁性质进行了表征,掺杂引起样品饱和磁化强度发生变化,这可能是因为Dy^3+取代引起的磁化强度增加和杂相引起的磁化强度降低共同作用的结果。四电极法研究隧道磁阻发现,磁阻与掺杂量的关系表现出降低-升高-降低的特殊变化规律。这主要是由于掺杂Fe3O4自旋极化率降低导致隧穿磁阻下降,同时,掺杂Fe3O4在隧穿颗粒体系中实现了第二相即绝缘相的同步合成,第二相的出现有利于隧穿磁阻的增加。 相似文献
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The title coordination polymer including two crystallographically independent Co2+ ions is hydrothermally synthesized, in which the Co(1) 2+ ion is four-coordinated by two carboxylate oxygen atoms from two different 5-(benzoic acid-4-yldiazenyl)isophthalate (byip3-) anions and two nitrogen atoms from two distinct 1,4-bis(imidazol-1-ylmethyl) benzene (bix) ligands displaying a tetrahedral geometry. The Co(2) 2+ ion is six-coordinated by two water molecules at the apical positions, and two carboxylate oxygen atoms and two nitrogen atoms at the equatorial positions, affording a slightly distorted octahedron. Two Co(1)2+ and two Co(2)2+ ions are linked together by four byip3- anions forming a 44-membered motif and these motifs are further arranged into a three-dimensional framework through bix ligands along the a axis with a larger channel (ca. 22.70×11.01). Each individual network interpenetrates with the other identical network in a parallel fashion to generate a 2-fold interpenetrating array with the {62.84}{63}2{64.82}2 topology. 相似文献
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A three-dimensional coordination polymer,[Ni(Hbyip2-)(bix)0.5(H2O)]n,has been hydrothermally synthesized.Each Ni2+ ion is five-coordinated by three carboxylate O atoms from three different 5-(benzoic acid-4-yldiazenyl)isophthalate(Hbyip2-) anions,one N atom from one 1,4-bis(imidazol-1-ylmethyl)benzene(bix) ligand and one O atom from an aqua ligand displaying a distorted square-pyramid.Each Ni atom is defined by three Hbyip2-anions and each Hbyip2-anion adopts a tris(mono-dentate) ligand coordinating to three Ni2+ ions affording a 36-membered inorganic ring.These rings are further arranged into an undulated two-dimensional layer parallel to the(101) plane.Adjacent two-dimensional networks are linked by bix ligands into a three-dimensional {63,83}{63} framework with a large channel(ca.26.3 × 13.6) along the [100] direction.Each individual {63,83}{63} network interpenetrates with two others in a parallel fashion to generate a 3-fold interpenetrating network. 相似文献
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合成了由六次甲基四胺与H3PMo12O40·nH2O,H4SiMo12O40·nH2O 和H4GeMo12 O40·nH2O 形成的具有二阶非线性光学性质的电荷转移盐,并由元素分析,红外光谱,电子光谱进行了表征。结果表明六次甲基四胺分子中有两个N 原子参与盐的形成,固体中阴阳离子之间存在强的相互作用;非线性光学性质研究表明,三种电荷转移盐的倍频效应分别为KDP和0.02 ,0 .11 和0.06 倍。 相似文献
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