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51.
A novel octamolybdate complex, [Fe(2,2-bipy)3]2[Mo8O26]·6H2Ohas been synthesized via the hydrothermal technique, and it crystallizes in monoclinic, space group P21/c with two molecules in a unit cell: a = 1.2 1 512(5), b = 1.36840(5), c = 2.18823(9) nm, β = 90.515( 1 )°, Mr = 2340.42, Z = 2, V = 3.6384(2) nm3, Dc = 2.136 g/cm3, F(000) = 2296, λ,(MoKα) = 0.071073 nm, μ = 1.813 mm 1, R =0.0719 and wR = 0.1093 for 4058 observed reflections with I≥2σ(I). The structure is characterized by the co-existence of octahedral [Fe(2,2′-bipy)3]2+ cations and β-octamolybdate [Mo8O26]4- anions. The magnetic susceptibility data show a Curie-Weiss paramagnetic behavior (θ = -5.201 K) in accordance with the spin-only ground state of Fe11 ions. IR, UV-Vis, and EPR spectra are also briefly noted in this paper.  相似文献   
52.
1 INTRODUCTION The chemistry of lanthanide (Ⅲ) complexes has a considerable history. The stereochemistry of the lanthanide (Ⅲ) complexes with ethyleneamine- N, N, N, N-tetraacetate (Edta) has been investigated[1~10]. Up to now, many Ln-Edta complexes with the chemical formulae of M[Ln(Edta)(H2O)m]nH2O (M = Na+, K+, Cs+, NH4+, Guanium; m = 2, 3; n = 0, 1, 3, 5) have been reported and suggested that the coordination modes and crystal systems for the Ln-Edta complexes depend on …  相似文献   
53.
1 INTRODUCTION The chemistry of mixed 15/16 main group compounds has attracted great attentions over the last years[1]. The metal chalcogenophosphides synthesized by solid state reactions[2] are the potential candidates for a wide range of applications such as semiconducting properties, two-dimensional magnetic behavior, anisotropy of conductivity and charge density waves. Some of these compounds are of lamellar structure, which are good materials for the investigation of intercalatio…  相似文献   
54.
1 INTRODUCTION During the past decade, a series of organic-inor- ganic hybrid compounds based on metal halide units have been prepared and studied[1]. The combination of organic and inorganic components at the mole- cular level affords us the opportunity to design new hybrid materials and modulate the properties of components[2]. As a result, some interesting proper- ties, such as non-linear optical[3], interesting magne- tic[4], efficient luminescence[2], ideal thermal and mechanical sta…  相似文献   
55.
1INTRODUCTION Chelidamic acid(2,6-dicarboxy-4-hydroxypyri-dine),an emblematical polydentate ligand,has been of great attraction due to its usage in many areas of science,such as coordinate chemistry,biochemis-try,organic chemistry,medical chemistry and even in HIV investigation[1].More and more metal com-plexes containing chelidamic acid ligands have been reported,which play a significant role in de-signing the molecules and extending chemistry of chelidamic acid[2].In our previous paper…  相似文献   
56.
1INTRODUCTIONTheuniqueelectronicpropertiesofcopperoxidesandoxyhalideshaveattractedmuchattentionduetotheirpotentialapplicationsassupercon-ductors,catalysts,luminescentmaterialsandp-typetransparentconductors[1].Inanefforttoexplorenewframeworkstructuresofmixed-metaloxyha-lidessuchasCuAgOCl,wehaveobtainedanewpolymorphofthebariumdicopperdisilicate,b-Ba2CuSi2O7.Inthispaper,wewillreportthesolid-statesynthesisandcrystalstructureofthisnewphaseanddiscussthedifferencesbetweenthestructuresofb-Ba2C…  相似文献   
57.
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   
58.
1 INTRODUCTION The picolinic acid (picH), also called pyridine- 2-carboxylic acid, has a broad spectrum of physio- logical effects on the activity functions of both ani- mal and plant organisms. It is attributed increasing interest due to its ability to …  相似文献   
59.
标题化合物是反应体系 (NH4) 3VS4/CoCl2 (PPh3) 2 /NEt4Cl在CH2 Cl2 中反应而得到的 ,单晶X射线结构分析表明 :其晶体属于立方晶系 ,化学式为C2 6 H35 NCl3CoP ,空间群为Pa3 ,Mr=5 5 7.84,a =17.80 7(5 ) ,V =5 6 46 .4 3,Z =8,Dc=1.31g/cm3,F(0 0 0 ) =2 32 8,μ(MoKα) =9.6cm- 1 ,R =0 .0 6 2 ,Rw =0 .0 6 7。标题化合物分子结构具有结晶学三次轴对称性 ,Co(II)原子为四面体配位 ,键角Cl-Co -Cl(113 .4(2 )°)大于键角Cl-Co -P(10 5 .2 (2 )°)。同时也讨论了标题化合物的电子光谱和变温磁化率  相似文献   
60.
兼具大的非线性光学(NLO)效应和高的激光损伤阈值(LIDT)是中远红外NLO材料领域最具挑战性的问题之一. 这里, 将碱金属离子K+引入到以黄铜矿AgGaS2为基底的材料中, 获得硫属化合物KAg3Ga8S14. 它的晶体结构采用与黄铜矿相类似的三维蜂窝状开放框架, 其中畸变四面体GaS4和AgS4以高度定向的方式排列, 产生中等的倍频效应 (0.4×AgGaS2 @1910 nm). 值得注意的是, 通过拓宽带隙(2.95 eV), 该化合物拥有高的激光损伤阈值(4.6×AgGaS2 @1064 nm). 此外, 通过理论计算表明四面体GaS4和AgS4决定硫属化合物KAg3Ga8S14的NLO光学性质.  相似文献   
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