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1.
In the search for potential ferroelectric materials, molecular‐based one‐, two‐ and three‐dimensional cadmium(II) organic–inorganic compounds have been of interest as they often display solid–solid phase transitions induced by a variation in temperature. A new cadmium dicyanamide complex, poly[4‐dimethylamino‐1‐ethylpyridin‐1‐ium [tri‐μ‐dicyanamido‐κ6N1:N5‐cadmium(II)]], {(C9H15N2)[Cd(C2N3)3]}n, was synthesized by the reaction of 4‐dimethylamino‐1‐ethylpyridin‐1‐ium bromide, cadmium nitrate tetrahydrate and sodium dicyanamide in aqueous solution. In the crystal structure, each CdII cation is octahedrally coordinated by six terminal N atoms from six anionic dicyanamide (dca) ligands. Neighbouring CdII cations are linked together by dicyanamide bridges to form a two‐dimensional coordination polymer. The organic cations are not involved in the formation of the supramolecular network.  相似文献   

2.
A cadmium–thiocyanate complex, poly[[bis(nicotinic acid‐κN)di‐μ‐thiocyanato‐κ2N:S2S:N‐cadmium(II)] monohydrate], {[Cd(NCS)2(C6H5NO2)2]·H2O}n, was synthesized by the reaction of nicotinic acid, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, each CdII cation is in a distorted octahedral coordination environment, coordinated by the N and S atoms of nicotinic acid and thiocyanate ligands. Neighbouring CdII cations are linked together by thiocyanate bridges to form a two‐dimensional network. Hydrogen‐bond interactions between the uncoordinated solvent water molecules and the organic ligands result in the formation of the three‐dimensional supramolecular network.  相似文献   

3.
A new cadmium–thiocyanate complex, namely catena‐poly[1‐carboxymethyl‐4‐(dimethylamino)pyridinium [cadmium(II)‐tri‐μ‐thiocyanato‐κ4N:S2S:N] [[[4‐(dimethylamino)pyridinium‐1‐acetate‐κ2O,O′]cadmium(II)]‐di‐μ‐thiocyanato‐κ2N:S2S:N]], {(C9H13N2O2)[Cd(NCS)3][Cd(NCS)2(C9H12N2O2)]}n, was synthesized by the reaction of 4‐(dimethylamino)pyridinium‐1‐acetate, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, two types of CdII atoms are observed in distorted octahedral coordination environments. One type of CdII atom is coordinated by two O atoms from the carboxylate group of the 4‐(dimethylamino)pyridinium‐1‐acetate ligand and by two N atoms and two S atoms from four different thiocyanate ligands, while the second type of CdII atom is coordinated by three N atoms and three S atoms from six different thiocyanate ligands. Neighbouring CdII atoms are linked by thiocyanate bridges to form a one‐dimensional zigzag chain and a one‐dimensional coordination polymer. Hydrogen‐bond interactions are involved in the formation of the supramolecular network.  相似文献   

4.
A cadmium–thiocyanate complex, poly[(1‐cyanomethyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane‐κ4N)octakis‐μ2‐thiocyanato‐κ8N:S8S:N‐tricadmium(II)], [Cd3(C8H14N3)2(NCS)8]n, was synthesized by the reaction of 1‐cyanomethyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane chloride, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, there are two independent types of CdII cation (one on a centre of inversion and one in a general position) and both are in distorted octahedral coordination environments, coordinated by N and S atoms from different ligands. Neighbouring CdII cations are linked together by thiocyanate bridges to form a two‐dimensional network. Hydrogen‐bonding interactions are involved in the formation of a three‐dimensional supramolecular network.  相似文献   

5.
In order to explore new metal coordination polymers and to search for new types of ferroelectrics among hybrid coordination polymers, two manganese dicyanamide complexes, poly[tetramethylammonium [di‐μ3‐dicyanamido‐κ6N1:N3:N5‐tri‐μ2‐dicyanamido‐κ6N1:N5‐dimanganese(II)]], {[(CH3)4N][Mn2(NCNCN)5]}n, (I), and catena‐poly[bis(butyltriphenylphosphonium) [[(dicyanamido‐κN1)manganese(II)]‐di‐μ2‐dicyanamido‐κ4N1:N5]], {[(C4H9)(C6H5)3P]2[Mn(NCNCN)4]}n, (II), were synthesized in aqueous solution. In (I), one MnII cation is octahedrally coordinated by six nitrile N atoms from six anionic dicyanamide (dca) ligands, while the second MnII cation is coordinated by four nitrile N atoms and two amide N atoms from six anionic dca ligands. Neighbouring MnII cations are linked together by μ‐1,5‐ and μ‐1,3,5‐bridging dca anions to form a three‐dimensional polymeric structure. The anionic framework exhibits a solvent‐accessible void of 289.8 Å3, amounting to 28.0% of the total unit‐cell volume. Each of the cavities in the network is occupied by only one tetramethylammonium cation. In (II), each MnII cation is octahedrally coordinated by six nitrile N atoms from six dca ligands. Neighbouring MnII cations are linked together by double dca bridges to form a one‐dimensional polymeric chain, and C—H...N hydrogen‐bonding interactions are involved in the formation of the one‐dimensional layer structure.  相似文献   

6.
As part of an exploration of new coordination polymers, a cadmium‐dicyanamide complex, namely poly[benzyltriethylammonium [tri‐μ‐dicyanamido‐κ6N 1:N5‐cadmium(II)]], {(C13H22N)[Cd(C2N3)3]}n , has been synthesized by the reaction of benzyltriethylammonium bromide, cadmium nitrate tetrahydrate and sodium dicyanamide in aqueous solution, and characterized by single‐crystal X‐ray diffraction at room temperature. In the crystal structure, each CdII cation is coordinated by six nitrile N atoms from six anionic dicyanamide (dca) ligands to furnish a slightly distorted octahedral geometry. Neighbouring CdII cations are linked by dicyanamide bridges to construct a two‐dimensional anionic layer coordination polymer. One amide N atom in the bridging dca ligand is disordered over two sites. The cations lie between the anionic frameworks and there are no hydrogen‐bond interactions between the cations and anions. The organic cations are not involved in the formation of the supramolecular network.  相似文献   

7.
The one‐ and two‐dimensional polymorphic cadmium polycarboxylate coordination polymers, catena‐poly[bis[μ2‐2‐(2‐methyl‐1H‐benzimidazol‐1‐yl)acetato‐κ3N3:O,O′]cadmium(II)], [Cd(C10H9N2O2)2]n, and poly[bis[μ2‐2‐(2‐methyl‐1H‐benzimidazol‐1‐yl)acetato‐κ3N3:O,O′]cadmium(II)], also [Cd(C10H9N2O2)2]n, were prepared under solvothermal conditions. In each structure, each CdII atom is coordinated by four O atoms and two N atoms from four different ligands. In the former structure, two crystallographically independent CdII atoms are located on twofold symmetry axes and doubly bridged in a μ2N:O,O′‐mode by the ligands into correspondingly independent chains that run in the [100] and [010] directions. Chains containing crystallographically related CdII atoms are linked into sheets viaπ–π stacking interactions. Sheets containing one of the distinct types of CdII atom are stacked perpendicular to [001] and alternate with sheets containing the other type of CdII atom. The second complex is a two‐dimensional homometallic CdII (4,4) net structure in which each CdII atom is singly bridged to four neighbouring CdII atoms by four ligands also acting in a μ2N:O,O′‐mode. A square‐grid network results and the three‐dimensional supramolecular framework is completed by π–π stacking interactions between the aromatic ring systems.  相似文献   

8.
Two cadmium halide complexes, catena‐poly[[chloridocadmium(II)]‐di‐μ‐chlorido‐[chloridocadmium(II)]‐bis[μ2‐4‐(dimethylamino)pyridin‐1‐ium‐1‐acetate]‐κ3O:O,O′;κ3O,O′:O], [CdCl2(C9H12N2O2)]n, (I), and catena‐poly[1‐cyanomethyl‐1,4‐diazoniabicyclo[2.2.2]octane [[dichloridocadmium(II)]‐μ‐oxalato‐κ4O1,O2:O1′,O2′] monohydrate], {(C8H15N3)[CdCl2(C2O4)]·H2O}n, (II), were synthesized in aqueous solution. In (I), the CdII cation is octahedrally coordinated by three O atoms from two carboxylate groups and by one terminal and two bridging chloride ligands. Neighbouring CdII cations are linked together by chloride anions and bridging O atoms to form a one‐dimensional zigzag chain. Hydrogen‐bond interactions are involved in the formation of the two‐dimensional network. In (II), each CdII cation is octahedrally coordinated by four O atoms from two oxalic acid ligands and two terminal Cl ligands. Neighbouring CdII cations are linked together by oxalate groups to form a one‐dimensional anionic chain, and the water molecules and organic cations are connected to this one‐dimensional zigzag chain through hydrogen‐bond interactions.  相似文献   

9.
A novel manganese coordination polymer, poly[(μ5‐thiophene‐3,4‐dicarboxylato)manganese(II)], [Mn(C6H2O4S)]n, was synthesized hydrothermally using 3,4‐thiophenedicarboxylate (3,4‐tdc2−) as the organic linker. The asymmetric unit of the complex contains an Mn2+ cation and one half of a deprotonated 3,4‐tdc2− anion, both residing on a twofold axis. Each Mn2+ centre is six‐coordinated by O atoms of bridging/chelating carboxylate groups from five 3,4‐tdc2− anions, forming a slightly distorted octahedron. The Mn2+ centres are bridged by 3,4‐tdc2− anions to give an infinite two‐dimensional layer which incorporates one‐dimensional Mn–O gridlike chains, and in which the 3,4‐tdc2− anion adopts a novel hexadentate chelating and μ5‐bridging coordination mode. The fully deprotonated 3,4‐tdc2− anion exhibits unexpected efficiency as a ligand towards the Mn2+ centres, which it coordinates through all of its carboxylate O atoms to provide the novel coordination mode. The IR spectrum of the complex is also reported.  相似文献   

10.
The structure of the title compound, catena‐poly[[cadmium(II)‐di‐μ‐chlorido‐μ‐(1,4‐diazoniabicyclo[2.2.2]octane‐1‐carboxylato)] [[aquachloridocadmium(II)]‐di‐μ‐chlorido] dihydrate], {[Cd(C8H15N2O2)Cl2][CdCl3(H2O)]·2H2O}n, contains two kinds of independent one‐dimensional chain, viz. {[Cd(C8H15N2O2)Cl2]+}n and {[CdCl3(H2O)]}n, and uncoordinated water molecules. Each CdII cation in the {[Cd(C8H15N2O2)Cl2]+}n chain is octahedrally coordinated by two pairs of bridging chloride ligands and two O atoms from different bridging carboxylate groups. CdII cations in the {[CdCl3(H2O)]}n chain are also octahedrally surrounded by four bridging chloride ligands, one terminal chloride ligand and one coordinated water molecule. Hydrogen bonds between solvent water molecules and these two independent chains generate a three‐dimensional framework containing two‐dimensional zigzag layers.<!?tpb=18pt>  相似文献   

11.
The title compound, {[Ag(C6H7AsNO3)(C18H15P)]·H2O}n, has been synthesized from the reaction of 4‐aminophenylarsonic acid with silver nitrate, in aqueous ammonia, with the addition of triphenylphosphane (PPh3). The AgI centre is four‐coordinated by one amino N atom, one PPh3 P atom and two arsonate O atoms, forming a severely distorted [AgNPO2] tetrahedron. Two AgI‐centred tetrahedra are held together to produce a dinuclear [Ag2O2N2P2] unit by sharing an O–O edge. 4‐Aminophenylarsonate (Hapa) adopts a μ3‐κ3N:O:O‐tridentate coordination mode connecting two dinuclear units, resulting in a neutral [Ag(Hapa)(PPh3)]n layer lying parallel to the (10) plane. The PPh3 ligands are suspended on both sides of the [Ag(Hapa)(PPh3)]n layer, displaying up and down orientations. There is an R22(8) hydrogen‐bonded dimer involving two arsonate groups from two Hapa ligands related by a centre of inversion. Additionally, there are hydrogen‐bonding interactions involving the solvent water molecules and the arsonate and amine groups of the Hapa ligands, and weak π–π stacking interactions within the [Ag(Hapa)(PPh3)]n layer. These two‐dimensional layers are further assembled by weak van der Waals interactions to form the final architecture.  相似文献   

12.
A homochiral helical three‐dimensional coordination polymer, poly[[(μ2‐acetato‐κ3O,O′:O)(hydroxido‐κO)(μ4‐5‐nicotinamido‐1H‐1,2,3,4‐tetrazol‐1‐ido‐κ5N1,O:N2:N4:N5)(μ3‐5‐nicotinamido‐1H‐1,2,3,4‐tetrazol‐1‐ido‐κ4N1,O:N2:N4:N5)dicadmium(II)] 0.75‐hydrate], {[Cd2(C7H5N6O)2(CH3COO)(OH)]·0.75H2O}n, was synthesized by the reaction of cadmium acetate, N‐(1H‐tetrazol‐5‐yl)isonicotinamide (H‐NTIA), ethanol and H2O under hydrothermal conditions. The asymmetric unit contains two crystallographically independent CdII cations, two deprotonated 5‐nicotinamido‐1H‐1,2,3,4‐tetrazol‐1‐ide (NTIA) ligands, one acetate anion, one hydroxide anion and three independent partially occupied water sites. The two CdII cations, with six‐coordinated octahedral and seven‐coordinated pentagonal bipyramidal geometries are located on general sites. The tetrazole group of one symmetry‐independent NTIA ligand links one of the independent CdII cations into 61 helical chains, while the other NTIA ligand links the other independent CdII cations into similar but unequal 61 helical chains. These chains, with a pitch of 24.937 (5) Å, intertwine into a double‐stranded helix. Each of the double‐stranded 61 helices is further connected to six adjacent helical chains through an acetate μ2‐O atom and the tetrazole group of the NTIA ligand into a three‐dimensional framework. The helical channel is occupied by the isonicotinamide groups of NTIA ligands and two helices are connected to each other through the pyridine N and carbonyl O atoms of isonicotinamide groups. In addition, N—H...O and O—H...N hydrogen bonds exist in the complex.  相似文献   

13.
In recent years, N‐heterocyclic carboxylate ligands have attracted much interest in the preparation of new coordination polymers since they contain N‐atom donors, as well as O‐atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. A new two‐dimensional coordination polymer, namely poly[[μ3‐2,2′‐(1,2‐phenylene)bis(4‐carboxy‐1H‐imidazole‐5‐carboxylato)‐κ6O4,N3,N3′,O4′:O5:O5′]manganese(II)], [Mn(C16H8N4O8)]n or [Mn(H4Phbidc)]n, has been synthesized by the reaction of Mn(OAc)2·4H2O (OAc is acetate) with 2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylic acid) (H6Phbidc) under solvothermal conditions. In the polymer, each MnII ion is six‐coordinated by two N atoms from one H4Phbidc2− ligand and by four O atoms from three H4Phbidc2− ligands, forming a significantly distorted octahedral MnN2O4 coordination geometry. The MnII ions are linked by hexadentate H4Phbidc2− ligands, leading to a two‐dimensional structure parallel to the ac plane. In the crystal, adjacent layers are further connected by N—H…O hydrogen bonds, forming a three‐dimensional structure in the solid state.  相似文献   

14.
In the dinuclear molecule of [(C5H4N)3N]2CdCl2CdCl2, one cadmium is octahedrally coordinated by a Cl2N4 donor set and the other cadmium is tetrahedrally coordinated by four chlorine atoms. The dinuclear units are connected by π–π interactions to give a two‐dimensional network. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

15.
The novel ZnII coordination polymer poly[{μ4‐2‐[3‐(pyridin‐2‐yl)‐1H‐pyrazol‐3‐yl]butanedioato}zinc(II)], [Zn(C12H9N3O4)]n, has been synthesized hydrothermally and structurally characterized. The results demonstrate that the complex shows two‐dimensional neutral wave‐like layers. The complex was prepared by the conjugate addition reaction of 2‐(1H‐pyrazol‐3‐yl)pyridine to cis‐fumaric acid in the presence of Zn(OAc)2·2H2O (OAc is acetate) at 413 K.  相似文献   

16.
One of the most interesting phenomena in coordination polymers (CPs) is the co‐existence of different interlaced motifs. However, CPs having two different interlaced motifs at the same time are still rare. Colourless block‐shaped crystals of the two‐dimensional polymer poly[[aqua(μ2‐naphthalene‐2,6‐dicarboxylato){μ2‐4,4′‐[oxybis(4,1‐phenylene)]dipyridine}cadmium(II)] monohydrate], {[Cd(C12H6O4)(C22H16N2O)(H2O)]·H2O}n , (I), was synthesized under hydrothermal conditions by the self‐assembly of 4,4′‐[oxybis(4,1‐phenylene)]dipyridine (OPY) with CdII in the presence of naphthalene‐2,6‐dicarboxylic acid (H2ndc). Each CdII ion is six‐coordinated by two N atoms from the pyridine rings of two OPY ligands and by four O atoms, three of which are from two ndc2− ligands and one of which is from a water molecule. In (I), every two identical two‐dimensional (2D) 63 layers are interpenetrated in a parallel fashion, resulting in an interesting 2D→2D framework with both polyrotaxane and polycatenane characteristics. The extension of these sheets into a three‐dimensional supramolecular net is via O—H…O hydrogen bonds. The solid‐state photoluminescence properties of (I) are also discussed.  相似文献   

17.
With regard to crystal engineering, building block or modular assembly methodologies have shown great success in the design and construction of metal–organic coordination polymers. The critical factor for the construction of coordination polymers is the rational choice of the organic building blocks and the metal centre. The reaction of Zn(OAc)2·2H2O (OAc is acetate) with 3‐nitrobenzoic acid (HNBA) and 4,4′‐bipyridine (4,4′‐bipy) under hydrothermal conditions produced a two‐dimensional zinc(II) supramolecular architecture, catena‐poly[[bis(3‐nitrobenzoato‐κ2O,O′)zinc(II)]‐μ‐4,4′‐bipyridine‐κ2N:N′], [Zn(C7H4NO4)2(C10H8N2)]n or [Zn(NBA)2(4,4′‐bipy)]n, which was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single‐crystal X‐ray diffraction analysis. The ZnII ions are connected by the 4,4′‐bipy ligands to form a one‐dimensional zigzag chain and the chains are decorated with anionic NBA ligands which interact further through aromatic π–π stacking interactions, expanding the structure into a threefold interpenetrated two‐dimensional supramolecular architecture. The solid‐state fluorescence analysis indicates a slight blue shift compared with pure 4,4′‐bipyridine and HNBA.  相似文献   

18.
A new cadmium dicyanamide complex, poly[tetramethylphosphonium [μ‐chlorido‐di‐μ‐dicyanamido‐κ4N1:N5‐cadmium(II)]], [(CH3)4P][Cd(NCNCN)2Cl], was synthesized by the reaction of tetramethylphosphonium chloride, cadmium nitrate tetrahydrate and sodium dicyanamide in aqueous solution. In the crystal structure, each CdII atom is octahedrally coordinated by four terminal N atoms from four anionic dicyanamide (dca) ligands and by two chloride ligands. The dicyanamide ligands play two different roles in the building up of the structure; one role results in the formation of [Cd(dca)Cl]2 building blocks, while the other links the building blocks into a three‐dimensional structure. The anionic framework exhibits a solvent‐accessible void of 673.8 Å3, amounting to 47.44% of the total unit‐cell volume. The cavities in the network are occupied by pairs of tetramethylphosphonium cations.  相似文献   

19.
The reaction of Cu(NO3)2·3H2O with 2,4′‐oxybis(benzoic acid) and 4,4′‐bipyridine under hydrothermal conditions produced a new mixed‐ligand two‐dimensional copper(II) coordination polymer, namely poly[[(μ‐4,4′‐bipyridine‐κ2N ,N ′)[μ‐2,4′‐oxybis(benzoato)‐κ4O 2,O 2′:O 4,O 4′]copper(II)] monohydrate], {[Cu(C14H8O5)(C10H8N2)]·H2O}n , which was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single‐crystal X‐ray diffraction. The X‐ray diffraction crystal structure analysis reveals that the CuII ions are connected to form a two‐dimensional wave‐like network through 4,4′‐bipyridine and 2,4′‐oxybis(benzoate) ligands. The two‐dimensional layers are expanded into a three‐dimensional supramolecular structure through intermolecular O—H…O and C—H…O hydrogen bonds. Furthermore, magnetic susceptibility measurements indicate that the complex shows weak antiferromagnetic interactions between adjacent CuII ions.  相似文献   

20.
Reaction of cadmium nitrate with diphenylphosphinic acid in dimethylformamide solvent yielded the one‐dimensional coordination polymer catena‐poly[[bis(dimethylformamide‐κO)cadmium(II)]‐bis(μ‐diphenylphosphinato‐κ2O:O′)], [Cd(C12H10O2P)2(C3H7NO)2]n, (I). Addition of 4,4′‐bipyridine to the synthesis afforded a two‐dimensional extended structure, poly[[(μ‐4,4′‐bipyridine‐κ2N:N′)bis(μ‐diphenylphosphinato‐κ2O:O′)cadmium(II)] dimethylformamide monosolvate], {[Cd(C12H10O2P)2(C10H8N2)]·C3H7NO}n, (II). In (II), the 4,4′‐bipyridine molecules link the CdII centers in the crystallographic a direction, while the phosphinate ligands link the CdII centers in the crystallographic b direction to complete a two‐dimensional sheet structure. Consideration of additional π–π interactions of the phenyl rings in (II) produces a three‐dimensional structure with channels that encapsulate dimethylformamide molecules as solvent of crystallization. Both compounds were characterized by single‐crystal X‐ray diffraction and FT–IR analysis.  相似文献   

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