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1.
The X-ray crystal structures of (NH4)2(15-crown-5)3[Cu(mnt)2] (1) and (NH4)2(benzo-15-crown-5)4- [Cu(mnt)2]·0.5H2O (2) were determined. Two single crystals are composed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2]2- anion. The triple-decker dication in complex 1 and a sandwich dimmer in complex 2 were observed. X-Band EPR studies on the single crystals of both complex 1 and complex 2 have been carried out at room temperature, which revealed that complex 2 showed a perfect hyperfine structure of Cu whereas that of complex 1 could not be observed. The principal values and direction cosines of the principal axes of the g and A tensors were computed by a least-squares fitting procedure. The spin density of Cu(Ⅱ) was estimated according to the principal values of the A tensors and compared well with the results calculated based on DFT method.  相似文献   

2.
用X射线衍射法测定了配合物(NH4)2(15-crown-5)3[Cu(mnt)2](1)及(NH4)2(benzo-15-crown-5)4[Cu(mnt)2]·0.5H2O(2)的晶体结构,两种配合物单晶分别由不同结构的冠醚超分子阳离子与[Cu(mnt)2]2-阴离子组成,配合物1呈三层夹心(triple-decker)双阳离子结构,配合物2的阳离子为三明治二聚物结构.两种配合物在X波段、室温下作了单晶电子顺磁共振(EPR)研究,配合物1没有检测到超精细结构,配合物2的EPR谱显示出Cu磁性核引起的超精细结构.用适于求非同轴的g和A张量的最小二乘法拟合技术严格计算了g张量和A张量的主值及其主轴的方向余弦,并计算了配合物2的Cu(Ⅱ)上的电子自旋密度分布,结果与用密度泛函理论(DFT)计算的值吻合.  相似文献   

3.
The common explosives, RDX (1,3,5-trinitro-1,3,5-triazacyclohexane), HMX (1,3,5,7- tetranitro-1,3,5,7-tetraazacyclooctane) and TNT (trinitrotoluene), were considered adequately for all weapons applications. Due to many catastrophic explosions resulting from unintentional initia-tion of impact, friction or shock, these explosives have become less attractive. TATB (1,3,5-tria- mino-2,4,6-trinitrobenzene) is noted for its insensitivity, however, it does not have the energetic performance of e…  相似文献   

4.
PreparahonofsomecomplexcomPOundsof[Pd(NH3)41X2tw,tvhereX=Cl-,Br,I-,X2=Co,:-,RdChl'-,etc.,wasdescribedasearlyl942l'].SynthesisandcryStalstIUCtUreOfthesaltSt'ithamons,Cr2o7",Cro.:',MoO"',andC,o'=',ttcrestillreportedmorcrecenh/'-'j.IPd(NH)4lX2,tvhereX=Cl',BrandNOz,isanotherkindofamndnepalladiumcomplexcompounds.IntheSyStemofIPd(NH).1"-Cl'-H2o,diamlltinedichloridepalladium(II)wasObtalnedbythereachonOfIPd(NH)4lHcomplexionwtthanutebydrogenchloride,andtetrachloridepalladiumaDbythe…  相似文献   

5.
1INTRODUCTION The construction of metal-organic coordination polymers based on covalent interactions[1]or supra-molecular contacts such as hydrogen-bonding and/orπ-πinteractions)[2]is now of great interest not only due to the enormous variety of intriguing structural topologies themselves,but also to their unexpected physical and chemical properties for potential prac-tical applications as functional materials.Many N-containing ligands,such as4,4?-bipyridine,2,2?-bi-pyridine and1,10-phen…  相似文献   

6.
In their report of the crystal structure of the compound claimed to be [Cu(OH)2(H2O)2(4- C5H4NCOOH)2], the authors did not give any experimental details on the location and refinement of the water and hydroxyl hydrogen atoms[1]; they had assumed the presence of the carboxylic -CO2H unit on the basis of the infrared stretching frequency at 1700 cm-1 that is only of medium intensity. The cell constants for the compound are, in fact, identical, with those documented for tetraaquabis(isonicot…  相似文献   

7.
在饱和硫酸铜液中滴入适量氨水,得深蓝色溶液,使其结晶,所得晶体是[Cu(NH_3)_4]SO_4还是[Cu(NH_3)_4](OH)_2呢?我们认为解决这个问题是需要实验的,为此我们进行了研究,现将所得结果总结成文,供同行们参考,不当处请指正。  相似文献   

8.
王美香  党振华  徐立 《结构化学》2010,29(4):551-554
A new tetracopper complex [Cu(H2O)3Cu(HCDTA)]2(ClO4)2·H2O (CDTA = transcyclohexane-1,2-diamine-N,N,N′,N′-tetraacetate) has been prepared and characterized by singlecrystal X-ray diffraction analysis. The crystal adopts space group C2/c with a = 16.990(10), b = 9.150(5), c = 29.318(17) , β = 104.289(9)°, V = 4417(4) 3, Z = 4, C28H52Cl2Cu4N4O31, Mr = 1265.80, Dc = 1.904 g/cm3, μ = 2.130 mm-1, F(000) = 2584, T = 293(2) K, the final R = 0.0328 and wR = 0.0809 for 4938 observed reflections (I 2σ(I)). The tetracopper units are interconnected by weak covalent bonds into a layered structure.  相似文献   

9.
1 INTRODUCTION The complexes of amino acid Schiff base have attracted considerable attention because of their bio- activities[1, 2]. Taurine is a special amino acid in be- ings, and recently the complexes of taurine conden- sation salicylaldehyde Schiff …  相似文献   

10.
The tetraaquabis(methylisonicotinate)zinc(II) disaccharinate [hereafter, [Zn(mein)2(H2O)4]·(sac)2], complex has been synthesized and characterized by spectroscopic IR, EPR and X-ray diffraction technique. The octahedral Zn(II) ion, which rides on a crystallographic centre of symmetry, is coordinated by two monodentate mein ligands through the ring nitrogen and four aqua ligands to form discrete [Zn(mein)2(H2O)4] unit, which captures two saccharinate ions in up and down positions, each through intermolecular hydrogen bonds. The magnetic environments of Cu2+ doped [Zn(mein)2(H2O)4]·(sac)2 complex have been identified by electron paramagnetic resonance (EPR) technique. EPR spectra of Cu2+ doped [Zn(mein)2(H2O)4]·(sac)2 single crystals have been studied between 113 and 300 K in three mutually perpendicular planes. The calculated results of the Cu2+ doped [Zn(mein)2(H2O)4]·(sac)2 indicate that Cu2+ ion contains two different complexes and each complexes are located in different chemical environments and each environment contains two magnetically inequivalent Cu2+ sites in distinct orientations occupying substitutional positions in the lattice. The vibrational spectra of this compound were discussed in relation to other compounds containing methyl isonicotinate and saccharinate complexes. The assignments of the observed bands were discussed.  相似文献   

11.
CrystalStructureof[Cu(C_(21)H_(25)N_2O_4)(H_2O)_2]·NO_3·2H_2OWuJie-Ying;XieFu-Xin;TianYu-Peng;ChenYao;NiShi-Sheng;DuShao-Wu;WuXin...  相似文献   

12.
LI  Ping  LIU  Zhihong 《中国化学》2009,27(11):2183-2189
Two novel organic base templated nonmetal borates [(CH3)2NH2]2[B5O6(OH)4]2·[HCON(CH3)2] ( ? ) and [NH3CH2CH2NH3]2[B14O20(OH)6] ( II ) have been synthesized under hydrothermal conditions, and characterized by elemental analyses, FT‐IR spectroscopy, X‐ray diffraction, and TG‐DTA. Their crystal structures were determined from single crystal X‐ray diffraction. The crystal structure of compound I is characterized by forming a 3D supramolecular structure with large channels along axes b and c through O? H···O hydrogen‐bonding among the [B5O6(OH)4]? anions. The crystal structure of compound II is characterized by forming a 3D supramolecular structure with large channels along axis a and direction [111] through O? H···O hydrogen‐bonding among the [B14O20(OH)6]4? anions. The templating organic amine cations in I and II are both obtained through in situ hydrothermal reactions, and are both located in the channels of the 3D supramolecular structure, respectively. Their thermal behavior has been also investigated.  相似文献   

13.
利用水热法首次合成了具有两种配位环境Cd原子的新型杂多蓝化合物[NH3(CH2)2NH3]5[Cd(H2O)][CdMo12ⅤO30(HPO4)6(H2PO4)2].5H2O.通过元素分析I、CP、TG和X射线单晶衍射确定了其组成,使用IR和EPR进行了结构表征.通过N2吸附脱附测定了比表面积和孔径,为催化研究提供了基础数据.结果表明:该晶体为三斜晶系,P-1空间群;晶胞参数a=1.200 2(2)nm,b=1.465 1(3)nm,c=2.119 2(4)nm,V=3.564 2(12)nm3,β=83.01(3)°,Z=2,F(000)=293 2,R1=0.030 0,wR2=0.071 6.  相似文献   

14.
CrystalStructureof[La(NO_3)_3(12-crown-4)-(H_2O)](12-crown-4)MaoJiang-Gao;JinZhong-Sheng;YuFeng-Lan(LaboratoryofRareEarthChemi?..  相似文献   

15.
1 INTRODUCTION Recently, the ternary or quaternary mixed anion complexes of cerium(III) containing 1,10-phenanthroline (phen) have attracted considerable attention due to their rich structural chemistry and appealing magnetic properties[1]. Panagiotopou…  相似文献   

16.
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   

17.
A new mononuclear Co(II) complex, [Co(hmz)2(H2O)4]·2H2O, has been synthesized by the reaction of Co(CH3COO)2·4H2O with 1-(4-hydroxyphenyl)-5-mercaptotetrazole (Hhmz). It crystallizes in the monoclinic system, space group P21/n with a = 13.502(5), b = 6.718(3), c = 13.972(6) , β = 117.532(4)o, V = 1123.9(8) 3, Z = 2, M r = 553.45, F(000) = 570, Dc = 1.635 g/cm3, μ = 1.008 mm–1, the final R = 0.0272 and wR = 0.0684 for 2194 observed reflections (I > 2σ(I)). The Co(II) is six-coordinated by two nitrogen atoms from two hmz–1 ligands and four water molecules, forming an octahedral geometry. The intermolecular hydrogen bonding and offset-panel π-π stacking interactions between the adjacent molecules extend the compound into a three- dimensional supramolecular framework. The title compound emits strong blue fluorescent light (λem(max) = 427 nm) at room temperature and is red-shifted compared with free ligand Hhmz (λem(max) = 342 nm).  相似文献   

18.
1INTRODUCTIONThepropensityforaggregationofformallyclosed-shelld10metalionsinpolynuclearcoordinationcom-plexesandsolid-statelatticeshaslongbeenrecog-nizedandexplored.Simultaneouslythesupramole-cularassemblyanddesignofmoleculeswithrichphotophysicalpropertieshavearousedgreatinter-est[1~4].Sincebis(diphenylphino)methane(dppm)ligandiswidelyusedfortheformationofpoly-nuclearmetalcomplexeswithmosttransitionmetalions[5~7],weutilizeddppmasabridgingligandtoreactwithsilveriodide,resultinginabicapped…  相似文献   

19.
1 INTRODUCTION The researches on 4,4?-bpy bridged transition me-tal coordination polymers (4,4?-bpy = 4,4?-bipyri-dine) assembled through covalent or hydrogen bondshave attracted great interest in the past decade due toits structural diversities and potential applications[1~5].So far a number of one-, two- and three-dimensio-nal coordination polymers containing N,N?-bidentatespacers with infinite chain[6, , diamond[4], rectangle[8~11], 7]T-shape[5, 12], ladder[13~15], octahedron[16] an…  相似文献   

20.
在很多生物代谢过程中,微量元素W起着关键作用,W与生物大分子结合形成具有特异功能的钨氧转移酶。1983年从热醋酸菌中提取了第一种钨酶,即甲酸脱氢酶,目前从生物体内提取的钨酶种类已达十二种之多,并发现钨氧转移酶与钼氧转移酶的活性结构因子呈相近性[1]。随着钨酶在生物体内的作用逐步得到重视,及其模拟的功能配合物在探究钨酶的生理活性和催化机理研究中所作的突出贡献,使钨氧转移酶活性结构因子的仿生合成、生理活性以及催化机理研究成为研究热点[2 ̄14]。根据报道显示,单分子的钨氧模拟配合物中W的价态只有WⅣ、WⅥ两种,且形成一个电…  相似文献   

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