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1.
本文讨论了I群-D2群V系数,给出在I群单值表示下的计算值。将以I群为出发点的群分解链延伸到其D2子群。还列出了D2群V系数的计算结果。  相似文献   

2.
Two lead(II)-thiocyanato coordination polymers with 5,5′-dimethyl-2,2′-bipyridine (5,5′-dm-2,2′-bpy) and 4,4′-dimethoxy-2,2′-bipyridine (4,4′-dmo-2,2′-bpy) as chelating ligands were synthesized and characterized by elemental analysis, IR and 1H-NMR spectroscopy, thermal behavior, and X-ray crystallography. These complexes have formulas [Pb(5,5′-dm-2,2′-bpy)(NCS)2] n (1) and [Pb(4,4′-dmo-2,2′-bpy)(NCS)2] n (2). The coordination numbers of PbII in 1 and 2 are four, PbN4, with “stereo-chemically active” electron pairs and hemidirected coordination spheres. Considering Pb···S as weak bonds, 1 and 2 are 1- and 2-D coordination polymers, respectively. The supramolecular features in these complexes are guided/controlled by weak directional intermolecular interactions.  相似文献   

3.
A new tetranuclear complex, {[Cu(phen)(OH)]4(H2O)2}?·?(SO4)2?·?8H2O (1) (phen = 1,10-phenanthroline), has been synthesized and characterized by elemental analysis, UV-Vis, IR, TG, and single-crystal X-ray diffraction. Complex 1 exhibits a 3-D supramolecular network with a 1-D metal–water chain consisting of tetranuclear hydroxo-bridged copper(II) clusters and water octamers and a 2-D water–sulfate layer containing cyclic water octamers with five types of O–H?···?O hydrogen-bonding motifs. The free ligand and its complex were screened for antibacterial activity against Gram-positive and Gram-negative bacteria.  相似文献   

4.
Two mononuclear metal-organic complexes, [Co(Hmpdc)2(H2O)4]·4H2O 1 and [Ni(Hfmpdc)2(H2O)4]·6H2O 2, were prepared from 2,6-dimethylpyridine-3,5-dicarboxylic acid (Hzmpdc) and 4-furyl-2,6-dimethylpyridine-3,5-dicarboxylic acid (H2fmpdc) with M(NO3)2 salts, respectively, and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and photoluminescent measurement. Complex 1 crystallizes in triclinic, space group P1 with a = 7.634(5), b = 8.695(5), c = 10.757(6)A, α = 69.647(7), β = 69.957(8), γ = 83.733(7)°, V = 628.9(7)A^3, Dc = 1. 561 g/cm^3,μ(MoKa) = 0.763 mm^-1, F(000) = 309, Z = 1, the final R = 0.0553 and wR = 0.1469 for 1909 observed reflections (Ⅰ 〉 2σ(Ⅰ)). Complex 2 crystallizes in monoclinic, space group P21/n with a = 9.5934(16), b = 12.422(2), c = 14.826(3) A, β = 105.201(2)°, V = 1705.0(5)A3, Dc = 1. 479 g/cm^3,μ(MoKa) = 0.655 mm^-1, F(000) = 796, Z = 2, the final R= 0.0351 and wR = 0.0889 for 2387 obsevved reflections (Ⅰ 〉 2σ(Ⅰ)). In the crystal structures of 1 and 2, diverse supramolecular motifs from 1-D chains/ladders to 3-D networks are constructed from corresponding distinct [M^Ⅱ(H2O)8] ion clusters as the second building units, respectively. The solid state compounds of 1 and 2 show similar photoluminescent spectra with emission maximum at ca.  相似文献   

5.
TheSynthesesof1┐Dimensional(1┐D)Chain,2┐DLayered,and3┐DMicroporousAlumino┐phosphateswithOccludedAmineorAmmoniumTemplatesfromA...  相似文献   

6.
The crystal structures and magnetic properties for two ion-pair complexes, [MG][Ni(dmit)2] (1) and [RhB][Ni(dmit)2] (2) (MG+ = N-(4-((4-(dimethylamino)phenyl)(phenyl)methylene)cyclohexa-2,5-dienylidene)-N-methylmethanaminium, RhB+ = 9-(2-carboxyphenyl)-3,6-bis(diethylamino)xanthylium; dmit2? = 1,3-dithiole-2-thione-4,5-dithiolate), have been investigated. Complex 1 crystallizes in the monoclinic space group P21/c, the stacking interactions between the GM+ and [Ni(dmit)2]? lead to the anion exhibiting a banana-shaped molecular geometry; the neighboring anions form a 1-D alternating chain along the crystallographic [1 1 0] direction via intermolecular lateral-to-lateral and head-to-head S ··· S contacts. The temperature dependence of magnetic susceptibility from 2–350 K does not display the magnetic character of a 1-D chain; the magnetic susceptibility data were fit to the Curie–Weiss equation to give C = 0.351(15) emu K mol?1, θ = ?3.51(28) K, and χ 0 = 8.00(3) × 10?5 emu mol?1. Complex 2 belongs to the triclinic space group P-1 with two crystallographic inequivalent [Ni(dmit)2]? anions, which exhibit perfect planar geometry. Two ethyl groups of RhB+ are disordered over two positions at 296 K, and one becomes ordered at 150 K. The [Ni(dmit)2]? anions form a 2-D molecular layer via intermolecular lateral-to-lateral and head-to-lateral S ··· S interactions with the anionic layer parallel to the crystallographic (0 1 ?1) plane. The temperature variation of magnetic susceptibility from 2 to 350 K shows that antiferromagnetic coupling dominates in the anionic layer, and the disorder–order changes of cationic structure are not coupled to magnetic property.  相似文献   

7.
8.
低熔点合金Sn-9Zn在无铅焊料中引人注目。然而,它与铜焊接的湿润性却很低,因此,它的应用受到很大限制。在合金中添加1%的稀土(如La和Ce,稀土Y,纯P,Al,Mg及Ti元素)对Sn-9Zn合金与铜焊接时影响其润湿性、氧化性和凝固性有待检验。本文实验表明,添加Al和Ti对湿润性有害,添加Mg,Y元素有稍好的改善,而添加稀土和P却有明显的改善,其氧化性也随添加稀土而增加,而添加P影响不大,凝固的Sn-9Zn合金表面粗糙,而Sn-37Pb却很光滑。  相似文献   

9.
Reaction of trans(N)-[Co(D-pen)2]? (pen = penicillaminate) or trans(N)-[Co(L-pen)2]? with [MCl2(L)] {M = Pd or Pt, L = 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen)} in the presence of tetrafluoroborate stereoselectively gave an optically active S-bridged dinuclear complex, [M(L){Co(D-pen)2}]BF4 · 2H2O or [M(L){Co(L-pen)2}]BF4 · 2H2O. The mixture of equimolar amounts of these enantiomers in H2O crystallizes as [M(L){Co(D-pen)2}]0.5[M(L){Co(L-pen)2}]0.5BF4 · 4H2O (DLbpyM · 4H2O, DLphenM-A · 4H2O), in which the enantiomeric complex cations are included by the ratio of 1 : 1. In crystals of DLbpyM · 4H2O and DLphenM-A · 4H2O, [M(L){Co(D-pen)2}]+ and [M(L){Co(L-pen)2}]+ interact stereospecifically with each other through π-conjugated systems to form dimeric structures. Other racemic crystals with the same chemical compositions as DLphenM-A · 4H2O, DLphenM-B · 4H2O, were obtained from equimolar amounts of [M(phen){Co(D-pen)2}]+ and [M(phen){Co(L-pen)2}]+ in aqueous acetonitrile solution. In the crystals of DLphenM-B · 4H2O, [M(phen){Co(D-pen)2}]+ and [M(phen){Co(L-pen)2}]+ are arranged alternately while overlapping phen planes, and the π electronic systems of phen interact with each other. Although stereospecific hydrogen bonds between the coordinated ?NH2 and ?COO? groups are formed in both DLphenM-A · 4H2O and DLphenM-B · 4H2O, their bonding modes differ noticeably from each other. As a result, DLphenM-A · 4H2O builds up 1-D ladder-like networks due to the stereospecific π–π stackings and hydrogen bondings between enantiomers, while 2-D sheet-like networks are established for DLphenM-B · 4H2O.  相似文献   

10.
氯甲基聚苯乙烯和2-氨基吡啶发生亲核取代反应,合成2-氨基吡啶修饰的聚苯乙烯树脂(简记为JX-08),以XAD-4树脂为参照,研究JX-08树脂对水溶液中2,4-D的吸附性能。实验结果表明,JX-08树脂在较宽的pH值范围(pH值在2~11)对2,4-D的吸附量大,XAD-4树脂在pH值小于2时对2,4-D的吸附量大;JX-08树脂对2,4-D的吸附符合Freundlich方程模型,XAD-4树脂对2,4-D的吸附符合Langmuir方程模型;当2,4-D流出液浓度为上样浓度的1%时,JX-08树脂和XAD-4树脂对2,4-D的吸附量分别为148.2mg/mL和40.5mg/m L。JX-08树脂和XAD-4树脂吸附的2,4-D可分别用6.5BV 2mol/L NaOH和6.5BV C2H5OH解吸。吸附机理表明,XAD-4树脂吸附2,4-D以疏水作用为主要推动力,而JX-08树脂对2,4-D的吸附存在阴离子交换和疏水作用,且阴离子交换对JX-08树脂吸附2,4-D的贡献大于疏水作用对JX-08树脂吸附2,4-D的贡献。  相似文献   

11.
Two new coordination polymers, {Ln2(hqda)3(H2O)4·6H2O}n (H2hqda = hydroquinone-O,O′-diacetic acid, Ln = Dy, 1; Ho, 2), were prepared and characterized by elemental analysis, IR spectroscopy, TG-DTA, fluorescence spectroscopy, and single-crystal X-ray diffraction. The two complexes are isomorphous with similar crystal structures. In 1 and 2, each Ln(III) ion is nine coordinate with seven oxygen atoms from hqda ligands and two oxygen atoms from water molecules. Two adjacent Ln(III) ions are bridged by–COO? groups from hqda ligands in bidentate-bridging and chelating-bridging modes. These building blocks cross link through OOCCH2OC6H4OCH2COO? spacers to form a 2–D network structure. The adjacent 2-D layers are further interlinked by hydrogen bonds to form a 3-D supermolecular structure.  相似文献   

12.
Two new Wells–Dawson based compounds containing alkali metals, [Ag(H2biim)2]2·[Ag5(H2biim)10Na2(H2O)2(H3/2P2W18O62)2]·12H2O (1) and [Cd(H2biim)2?K(P2W18O62)1/2] (2) (H2biim?=?2,2′-biimidazole), have been synthesized under hydrothermal conditions. In 1, two-supporting Wells–Dawson anions are linked by a [Ag(H2biim)2]+ subunit to form a dimer. The adjacent dimers are further connected by Na+ through (POM)O-Na-O(POM) bonds to build a 1-D chain. In 2, adjacent anions are linked by two [Cd2(H2biim)2]4+ subunits and a 1-D chain is formed. Furthermore, the anion in the chain is fused by six K+ ions and a 3-D framework is obtained. The alkali metals exhibit crucial influence on the conversion of dimensionality assisting anions and Ag-H2biim subunits to construct 1-D and 3-D frameworks. The electrochemical and photocatalytic properties of 1 and 2 have been investigated.  相似文献   

13.
Three novel organic-inorganic hybrid borotungstates {[Ni(phen)2(H2O)]2H(α-BW12O40)}·4H2O (1), [CuI(2,2'-bipy)(4,4′-bipy)0.5]2{[CuI(2,2′-bipy)]2CuI(4,4′-bipy)2(α-BW12O40)} (2) and {[CuI(4,4′-bipy)]3H2(α-BW12O40)}·3.5H2O (3) (phen=1,10-phenanthroline, 2,2′-bipy=2,2′-bipyridine, 4,4′-bipy=4,4′-bipyridine) have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, UV spectra, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), single-crystal X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and photoluminescence. The structural analysis reveals that 1 consists of a 0-D bisupporting polyoxometalate cluster where two [Ni(phen)2(H2O)]2+ cations are grafted on the polyoxoanion [α-BW12O40]5- through two terminal oxygen atoms, 2 shows a 1-D infinite chain constructed from [α-BW12O40]5- polyoxoanions and {[CuI(2,2′-bipy)]2CuI(4,4′-bipy)2}3+ cations by means of alternating fashion, and 3 displays an unprecedented 2D extended structure built by [α-BW12O40]5- polyoxoanions and -CuI-4,4′-bipy- linear chains, in which each [α-BW12O40]5- polyoxoanion acts as a tetradentate inorganic ligand and provides three terminal oxygen atom and one two-bridging oxygen atom. The presence of NiII and WVI in 1, CuI ions and WVI in 2 and 3 are identified by XPS spectra. The photoluminescence of 2 and 3 are also investigated.  相似文献   

14.
1 INTRODUCTION In the design of crystal molecule, inorganic crystal engineering is one of the focused fields that are ever developing[1]. The introduction of different metal ions and bridging ligands often gives rise to novel physical and chemical properties[2~4]. Conse- quently, the supramolecular compounds constructed from weak interactions, such as hydrogen bond, π-π stacking, C–H???O interaction, ion-π interaction and hy- drophobing interaction, have become the new focus of cryst…  相似文献   

15.
The complex [Cu2(H2dhbd)2(tpy)2]·CH3OH·4H2O 1 (H4dhbd =2,3-dihydroxybutanedioic acid, tpy = 2,2':6',2''-terpyridine) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis. The crystal is of triclinic, space groups Pi with a= 8.6859(17), b = 11.223(2), c = 12.275(2)A, α = 112.454(3), β= 98.435(3), γ = 105.593(3)°, V= 1022.5(3) A^3, Z = 1, C38H42Cu2N6O18, Mr = 997.86, Dc = 1.621 g/cm^3, μ= 1.127 mm^-1, F(000) = 514, T = 293(2) K, the final R = 0.0539 and wR = 0.1394 for 3550 observed reflections with I 〉 2σ(I). In the dinuclear unit, two Cun atoms are bridged by two H2dhbd chelate anions, forming a 14-membered ring, in which the distance of Cu…Cu atoms is 7.0526(12)A. Adjacent dinuclear units are constituted through π-π interactions and C-H…O hydrogen-bonding interactions, fashioning the final 3-D supramolecular framework with 1-D open channels. Variable-temperature magnetic susceptibility measurement indicates the presence of weak antiferromagnetic exchange interactions between Cu^II ions.  相似文献   

16.
One-pot solvothermal reaction of Iransition metal Znn salt with 4,4-bipyddyl (bpy) and 1,4-benzenediacrylic add (H2L) in the presence of Et3N generates a three-dimensional (3-D) supramolecular network with 1-D cation metal-organic coordination polymer, [Zn(H20)a(bpy)]-L 1, and structurally characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and photoluminescent property. The complex crystallizes in triclinic, space group P1 with a = 7.1291(2), b = 7.3784(3), c = 10.5042(3)A, α = 95.049(2), β = 102.162(2), 7 = 97.027(3)0, V= 532.38(3)A3, C22H24N2O8Zn, Mr = 509.82, De= 1.590 g/cm3, p(MoKa)= 1.207 ram-l, F(000) = 264, Z = 1,the finalR=O.0438and wR=O.lOll for 1589 observed reflections (I 〉 2σ(I)). In the crystal structure, the second building unit composed of [Zn(H2O)4].L constructs two distinct 2-D supramolecular sheets and a neutral 3-D architecture. The title compound 1 shows strong photoluminescence with emission maximum at 2 = 455 nm upon λex.max = 355 nm.  相似文献   

17.
1 INTRODUCTION The design and synthesis of metal-organic frame- work structures have been extensively studied owing to the potential discovery of novel functional ma- terials to be applied in the areas of absorption, ca- talysis, optics sensors, magnetism and molecular recognition[1~5]. The generation of supramolecular frameworks rests on the coordination geometry of metal ion, structural characteristics of organic ligand, solvent system and counter ion[6~10]. The most useful strategy to…  相似文献   

18.
A novel Cd(Ⅱ) coordination polymer,{[Cd3(tzo)2(suc)(H2O)6]·(suc)}n (Htzo = 1,2,4-triazole,H2suc = succinic acid),has been synthesized from the reaction of aqueous solution of niques,and structurally characterized by X-ray analysis and spectral techniques.To the best of our knowledge,among the few documented triazole-cadmium coordination polymers,this complex presents a novel configuration.The deprotonated 1,2,4-triazole is in tridentate and succinate in bis-chelate modes to link the Cd(Ⅱ) centers,generating a 2-D grid-like network topology.Thermogravimetric analysis results show that the framework architecture is a stable porous material.The fluorescent emission has also been discussed.  相似文献   

19.
A complete NMR study involving both 1D and 2D 13C-{103Rh} and 31P-{103Rh} HMQC measurements, on [Rh6C(CO)14(PPh3)]2- are reported and discussed, together with the multiple Rh quantum effects found for resonances associated with edge- and face-bridging CO's. As found in [Rh6C(CO)15]2-, the carbonyl ligands in [Rh6C(CO)14(PPh3)]2- undergo CO-intermolecular exchange with 13CO at different rates; for the edge-bridging CO's, the lower the value of 1J(Rh–CO), the faster the rate of intermolecular exchange with 13CO.  相似文献   

20.
Two metal–organic coordination polymers, [Cu3(4-bpcb)2(1,2,4-btc)2(H2O)2] (1) and [Cu3(3-bpcb)3(btec)1.5] (2), have been synthesized from hydrothermal reaction of copper chloride with mixed ligands [4-bpcb?=?N,N′-bis(4-pyridinecarboxamide)-1,4-benzene, 3-bpcb?=?N,N′-bis(3-pyridinecarboxamide)-1,4-benzene, 1,2,4-H3btc?=?1,2,4-benzenetricarboxylic acid, and H4btec?=?1,2,4,5-benzenetetracarboxylic acid]. X-ray diffraction analysis reveals that 1 exhibits a 2-D layer structure and 2 possesses a three-dimensional (3-D) network. In 1 and 2, CuII ions are connected by bridging 1,2,4-btc or btec to form 2-D polymeric layers. Cu-1,2,4-btc layer does not propagate into a 3-D coordination framework in 1 due to 4-bpcb showing monodentate coordination (via ligation of only one pyridyl nitrogen). In 2, Cu-btec 2-D layers are further extended into a 3-D network with (64.82)3 topology by 3-bpcb ligand in μ 2-bridging coordination (via ligation of two pyridyl nitrogens). The different structures of the two complexes illustrate the influence of different polycarboxylates and N-donor positions of organic ligands on the formation of such coordination architectures. Moreover, the thermal properties and electrochemical properties of the copper complexes bulk-modified carbon paste electrodes have been studied.  相似文献   

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