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1.
The crystal structure and the electronic properties of YbGa2 realising a CaIn2 type atomic arrangement were characterised at ambient conditions using single crystal X‐ray diffraction data and magnetic susceptibility measurements at ambient pressure. Pressure‐induced changes of structural and electronic properties of YbGa2 were measured by means of angle‐dispersive X‐ray powder diffraction and XANES at the Yb LIII threshold. At pressures above 22(2) GPa, YbGa2 undergoes a structural phase transition into a high pressure modification with a UHg2 type crystal structure. Parallel to the pressure‐induced structural alterations, ytterbium in YbGa2 undergoes an increase of the oxidation state from +2 at ambient conditions to +3 in the high‐pressure phase. Quantum chemical calculations of the Electron‐Localisation‐Function confirm that the phase transition is associated with a conversion of the three‐dimensional gallium network of the low‐pressure crystal structure into two‐dimensional gallium layers in the high‐pressure modification.  相似文献   

2.
The title compound, [Mn(C10H8O5S)(H2O)4]n, a one‐dimensional manganese(II) complex comprising helical chains bridged by 4‐(carboxylatomethylsulfanyl)phenoxyacetate ligands has been characterized by single‐crystal X‐ray diffraction analysis. Hydrogen‐bonding inter­actions between adjacent chains extend the complex into a three‐dimensional supra­molecular architecture.  相似文献   

3.
A new tetrazole–metal supramolecular compound, di‐μ‐chlorido‐bis(trichlorido{1‐[(1H‐tetrazol‐5‐yl‐κN2)methyl]‐1,4‐diazoniabicyclo[2.2.2]octane}cadmium(II)), [Cd2(C8H16N6)2Cl8], has been synthesized and structurally characterized by single‐crystal X‐ray diffraction. In the structure, each CdII cation is coordinated by five Cl atoms (two bridging and three terminal) and by one N atom from the 1‐[(1H‐tetrazol‐5‐yl)methyl]‐1,4‐diazoniabicyclo[2.2.2]octane ligand, adopting a slightly distorted octahedral coordination geometry. The bridging bicyclo[2.2.2]octane and chloride ligands link the CdII cations into one‐dimensional ribbon‐like N—H...Cl hydrogen‐bonded chains along the b axis. An extensive hydrogen‐bonding network formed by N—H...Cl and C—H...Cl hydrogen bonds, and interchain π–π stacking interactions between adjacent tetrazole rings, consolidate the crystal packing, linking the poymeric chains into a three‐dimensional supramolecular network.  相似文献   

4.
The crystal structure of the gadolinium iron bismuthide Gd6FeBi2 has been characterized by single‐crystal X‐ray diffraction data and analyzed in detail using first‐principles calculations. The structure is isotypic with the Zr6CoAl2 structure, which is a variant of the ZrNiAl structure and its binary prototype Fe2P (Pearson code hP9, Wyckoff sequence g f d a). As such, the structure is best viewed as an array of tricapped trigonal prisms of Gd atoms centered alternately by Fe and Bi. The magnetic‐ordering temperature of this compound (ca 350 K) is much higher than that of other rare‐earth metal‐rich phases with the same or related structures. It is also higher than the ordering temperature of many other Gd‐rich ternary phases, where the magnetic exchange is typically governed by Ruderman–Kittel–Kasuya–Yosida (RKKY) interactions. First‐principles calculations reveal a larger than expected Gd magnetic moment, with the additional contribution arising from the Gd 5d electrons. The electronic structure analysis suggests strong Gd 5d–Fe 3d hybridization to be the cause of this effect, rather than weak interactions between Gd and Bi. These details are of importance for understanding the magnetic response and explaining the high ordering temperature in this material.  相似文献   

5.
Three metal coordination polymers {[Co(L)2(H2O)2]2+ · 2NO3}n ( 1 ), {[Mn(L)2(H2O)2]2+ · 2Cl · 3H2O}n ( 2 ), and [ZnL(ba)2]n ( 3 ) [L = 3,5‐bis(imidazole‐1‐yl)pyridine and Hba = benzoic acid] were synthesized and structurally characterized by IR spectroscopy, elemental analysis, X‐ray powder diffraction, and X‐ray single crystal diffraction. Complex 1 shows a one‐dimensional (1D) chain structure. Adjacent chains are connected by hydrogen bonding and nitrate groups to form a 3D network. Complex 2 features a 2D layer structure. A three‐dimensional network is constructed through the cluster consisting of two chloride ions and three water molecules. Complex 3 shows a 1D zigzag chain structure that further twists together to form a 3D network. The X‐ray powder diffraction patterns were compared with the simulated ones. Moreover, the luminescent properties of 1 – 3 were investigated in the solid state at room temperature, and the thermogravimetric analyses were carried out to study the thermal stability of the three complexes.  相似文献   

6.
The reaction of CoSO4 with 2,4‐oxydibenzoic acid (H2oba) and 4,4′‐bipyridine (bipy) under hydrothermal condition yielded a new one‐dimensional cobalt(II) coordination polymer, {[Co(C14H9O5)2(C10H8N2)(H2O)2]·2H2O}n, which was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, magnetic properties and single‐crystal X‐ray diffraction. The CoII ions are connected by bipy ligands into infinite one‐dimensional chains. The Hoba ligands extend out from the two sides of the one‐dimensional chain. O—H...O hydrogen bonding extends these chains into a two‐dimensional supramolecular architecture.  相似文献   

7.
A new ternary monocopper(II) complex with co‐ligands of 2,2′‐diamino‐4,4′‐bithiazole (dabt) and picrate (pic), namely [Cu(dabt)(pic)2], has been synthesized and characterized using elemental analyses, molar conductance measurements, infrared and electronic spectral studies and single‐crystal X‐ray diffraction. The crystal structure analyses revealed that the copper(II) ion has a {CuN2O4} distorted octahedral coordination environment. The hydrogen bonding interactions contribute to a three‐dimensional supramolecular structure in the crystal. The reactivity towards herring sperm DNA showed that the copper(II) complex can interact with DNA in the mode of intercalation. The molecular docking of the complex with DNA sequence d(ACCGACGTCGGT)2 demonstrated that the copper(II) complex is stabilized by hydrogen bonding interaction. The in vitro anticancer activities suggested that the copper(II) complex is active against selected tumor cell lines. The effects of the two co‐ligands in the copper(II) complex on DNA‐binding events and in vitro anticancer activity are preliminarily discussed. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

8.
The title compound, {[Cu(C10H8N2)(H2O)](C8H4O4)0.5·H2O}n, has been synthesized hydro­thermally and characterized by single‐crystal X‐ray diffraction. The compound consists of nearly linear one‐dimensional chains of [Cu(4,4′‐bipy)(H2O)]nn+ cations (4,4′‐bipy is 4,4′‐bipyridyl), surrounded by isophthalate anions and free water mol­ecules. Hydro­gen‐bonding interactions involving cationic chains, isophthalate anions and free water mol­ecules lead to the formation of a three‐dimensional network structure.  相似文献   

9.
A new mixed‐ligand complex, [CdL(bipy)(CH3OH)(NO3)]n ( 1 ), (HL = 4‐amino‐1‐naphthalene sulfonic acid and bipy = 4,4′‐bipyridine) could be achieved by combining d10 Cd2+ to HL and bridging ligand 4,4′‐bipy. The structure is characterized by X‐ray single‐crystal diffraction. 4‐amino‐1‐naphthalene sulfonate and 4,4′‐bipyridine act as bridging ligands, linking two adjacent CdII atom to form a two‐dimensional coordination polymer, respectively. N‐H···O hydrogen‐bonding interaction between these networks to form the face‐to‐face three‐dimensional architecture. By carrying out the reaction of polymeric cadmium naphthalene sulfonate with Na2S in the presence of sodium hydroxide, scalelike CdS materials have been obtained. The structure has been characterized by scanning electron microscopy and powder X‐ray diffraction.  相似文献   

10.
Single crystals of the high‐temperature modification of zinc catena‐polyphosphate, β‐Zn(PO3)2, were grown from a melt and quenched from 1093 K to room temperature. The structure was solved from single‐crystal X‐ray diffraction data and is built of corrugated (PO3) polyphosphate chains, which extend along the c direction with an eight‐tetrahedra repeat. Slightly distorted [ZnO4] tetrahedra link the polyphos­phate chains into a three‐dimensional network.  相似文献   

11.
Ca3Pd4Bi8: Crystal and Electronic Structure Ca3Pd4Bi8 (a = 10.814(4), b = 17.050(6), c = 4.149(4) Å) was prepared by heating the elements at 900 °C and investigated by single crystal X‐ray methods. The compound crystallizes in a new structure type (Pbam; Z = 2). Six Bi atoms form distorted trigonal prisms around the Pd atoms. The polyhedra share common corners, edges or faces building up a three dimensional Pd, Bi network, whose holes are occupied by Ca atoms. A special feature is a distorted octahedron of four Pd and two Bi atoms connected via short homonuclear bonds. The metallic behaviour of the compound derived from the bond lengths is discussed by LMTO band structure calculations.  相似文献   

12.
The title two‐dimensional coordination polymer, [Na(C2H8NO6P2)]n, was characterized using powder X‐ray diffraction data and its structure refined using the Rietveld method. The asymmetric unit contains one Na+ cation and one (1‐azaniumylethane‐1,1‐diyl)bis(hydrogen phosphonate) anion. The central Na+ cation exhibits distorted octahedral coordination geometry involving two deprotonated O atoms, two hydroxy O atoms and two double‐bonded O atoms of the bisphosphonate anion. Pairs of sodium‐centred octahedra share edges and the pairs are in turn connected to each other by the biphosphonate anion to form a two‐dimensional network parallel to the (001) plane. The polymeric layers are connected by strong O—H...O hydrogen bonding between the hydroxy group and one of the free O atoms of the bisphosphonate anion to generate a three‐dimensional network. Further stabilization of the crystal structure is achived by N—H...O and O—H...O hydrogen bonding.<!?tpb=18.7pt>  相似文献   

13.
利用水热法合成了两种新型的二维(2D)稀土配位聚合物[Ln(PDC)(OH)(H2O)2]n (Ln = Eu (1) and Tb (2), H2PDC = 3,4-吡啶二羧酸),通过元素分析、红外光谱、热分析和X射线单晶衍射等技术对其进行了表征。单晶结构分析表明这两种配合物都显示出包含有一维Ln-O-Ln链的二维层状结构,层间又进一步通过 π-π 堆积和氢键作用扩展成三维超分子网络结构。此外,这两种配合物的固体在室温下都有强的荧光发射。  相似文献   

14.
王瑞虎  洪茂椿  翁家宝  曹荣  罗军华 《中国化学》2002,20(10):1124-1128
IntroductionDesignandsynthesesofnovelsupramolecularcom plexeswithunusualandtailorablestructuresarefunda mentalstepsindiscoveryandfabricationofvarioustech nologicallyusefulfunctionalsupramoleculardevices .1 3Recently ,considerableeffortshavebeendevotedtocr…  相似文献   

15.
A new thallium‐based supramolecular polymer [Tl(μ3–3‐HClb)(μ3–3‐Clb)]n ( 1 ), (3‐HClb = 3‐chloroperbenzoic acid), has been synthesized and structurally characterized by single crystal X‐ray crystallography. It has a two‐dimensional structure with linear thallophilic and covalent hydrogen‐bonding interactions. In order to evaluate the effects of concentration, ultrasonic irradiation and type of solvents on structure, morphology and thermal behavior of 1 , some experiments were designed, and eight samples of 1 were synthesized under different conditions. These samples were characterized by IR spectroscopy, thermogravimetric and differential thermal analyses, X‐ray powder diffraction and scanning electron microscopy.  相似文献   

16.
The title compound, C25H35N3O2, is a novel urea derivative. Pairs of intermolecular N—H...O hydrogen bonds join the molecules into centrosymmetric R22(12) and R22(18) dimeric rings, which are alternately linked into one‐dimensional polymeric chains along the [010] direction. The parallel chains are connected via C—H...O hydrogen bonds to generate a two‐dimensional framework structure parallel to the (001) plane. The title compound was also modelled by solid‐state density functional theory (DFT) calculations. A comparison of the molecular conformation and hydrogen‐bond geometry obtained from the X‐ray structure analysis and the theoretical study clearly indicates that the DFT calculation agrees closely with the X‐ray structure.  相似文献   

17.
Cyanide as a bridge can be used to construct homo‐ and heterometallic complexes with intriguing structures and interesting magnetic properties. These ligands can generate diverse structures, including clusters, one‐dimensional chains, two‐dimensional layers and three‐dimensional frameworks. The title cyanide‐bridged CuII–CoIII heterometallic compound, [CuIICoIII(CN)6(C4H11N2)(H2O)]n, has been synthesized and characterized by single‐crystal X‐ray diffraction analysis, magnetic measurement, thermal study, vibrational spectroscopy (FT–IR) and scanning electron microscopy/energy‐dispersive X‐ray spectroscopy (SEM–EDS). The crystal structure analysis revealed that it has a two‐dimensional grid‐like structure built up of [Cu(Hpip)(H2O)]3+ cations (Hpip is piperazinium) and [Co(CN)6]3− anions that are linked through bridging cyanide ligands. The overall three‐dimensional supramolecular network is expanded by a combination of interlayer O—H...N and N—H...O hydrogen bonds involving the coordinated water molecules and the N atoms of the nonbridging cyanide groups and monodentate cationic piperazinium ligands. A magnetic investigation shows that antiferromagnetic interactions exist in the title compound.  相似文献   

18.
Two novel one‐ and two‐dimensional network structure bismuth(III) complexes with N, N‐di(2‐hydroxylethyl)‐aminodithiocarboxylate, {Bi[S2CN(C2H4OH)2]2[1, 10‐Phen]2(NO3)}·3H2O (1) and (Bi[S2CN(C2H4OH)2]3)2 (2) were synthesized. Their crystal and molecular structures were determined by X‐ray single crystal diffraction analysis. The crystal 1 belongs to monoclinic system with space group C2/c, a=1.6431(7) nm, b=2.4323(10) nm, c= 1.2646(5) nm, β=126. 237(5), Z=4, V=4.076(3) nm3, Dc=1.757 Mg/m3, μ=4.598 mm?1, F(000)=2156, R= 0.0211, wR=0.0369. The structure shows a distorted square antiprism configuration with eight‐coordination for the central Bi atom. The one‐dimensional chain structure was formed by H‐bonding interaction between hydroxyl group of N, N‐di(2‐hydroxylethyl)aminodithiocarboxylate ligands and crystal water. The crystal 2 belongs to monoclinic system with space group p2(1)/c, a= 1.1149(4) nm, b=2.1274(8) nrn, c=2.2107(8) nm, β=98.325(8)°, 2=4, V=5. 188(3) nm3, Dc=1.920 Mg/m3, μ=7.315 mm?1, F(000)=2944, R=0.0565, wR=0.0772. The structure shows a distorted square antiprism configuration with eight‐coordination for the central Bi atoms. The two‐dimensional network structure was formed by H‐bonding interaction between adjacent molecules.  相似文献   

19.
A new manganese(II) complex [Mn3(bidc)2(C2O4)(H2O)10]n ( 1 ) (bidc = benzimidazole‐5,6‐dicarboxylate) was synthesized and characterized by X‐ray crystallography. X‐ray diffraction shows that complex 1 has a neutral, one‐dimensional (1D) brick wall chain structure. With the intramolecular and intermolecular hydrogen bonding interactions, the adjacent chains are joined into a 3D suparmolecular architecture. IR spectroscopy and variable temperature magnetic susceptibility measurements were made, which indicated weak antiferromagnetic coupling between the MnII ions in complex 1 .  相似文献   

20.
The title complex salt, transanti‐[CrBr2(Me2tn)2]ClO4 (where Me2tn = 2,2‐dimethylpropane‐1,3‐diamine, C5H14N2), was prepared and its structure determined by single‐crystal X‐ray diffraction at 100 K. The asymmetric unit contains three conformationally similar complex cations and three perchlorate anions. In each complex cation, the CrIII centre is coordinated by four N atoms of two chelating Me2tn ligands in the equatorial plane and by two Br atoms in a trans‐axial arrangement, to give a distorted octahedral geometry. Interionic contacts are dominated by extensive hydrogen bonding, involving the NH groups of the Me2tn ligand as donors and the anion O atoms or coordinated Br atoms as acceptors, resulting in two‐dimensional layers in the bc plane. Ligand field analysis based on the angular overlap model, and IR and electronic spectroscopic properties, are also discussed.  相似文献   

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