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One-dimensional Chains (one-dimensional + chain)
Terms modified by One-dimensional Chains Selected AbstractsUnusual T4(1) Water Chain Stabilized in the One-Dimensional Chains of a Copper(II) Coordination PolymerEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2007Yi Jin Abstract A novel T4(1) water chain in a new CuII coordination polymer, {[Cu(C4H6N2)2(C4H2O4)] (H2O)3}n (1, where C4H6N2 = 2-methylimidazole, C4H2O4 = maleate), has been synthesized and structurally characterized by single-crystal X-ray diffraction. Thermogravimetry, infrared spectroscopy, elemental analysis, and magnetic analysis have also been used to characterize 1. Complex 1 crystallizes in the trigonal space group P3221, and the 1-D chains composed of cyclic water tetramers play an important role in stabilizing the overall polymeric structure. Furthermore, this 1-D water chain presents an unusual association mode of water molecules.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Innentitelbild: Poly(polyoxotungstate)s with 20 Nickel Centers: From Nanoclusters to One-Dimensional Chains (Angew. Chem.ANGEWANDTE CHEMIE, Issue 39 200939/2009) Die bislang größte Zahl an Nickelionen in Polyoxometallaten erreichten G.-Y. Yang et,al. in der Zuschrift auf S.,7312,ff. Die beiden größten nickelsubstituierten Poly(polyoxowolframate) werden durch Abbaureaktionen und mithilfe des strukturdirigierenden Einflusses trilakunarer Keggin-{B-, -PW9O34}-Fragmente unter Hydrothermalbedingungen in Gegenwart von Nickelionen synthetisiert. [source] Poly(polyoxotungstate)s with 20 Nickel Centers: From Nanoclusters to One-Dimensional Chains,ANGEWANDTE CHEMIE, Issue 39 2009Shou-Tian Zheng Aufgereiht: Unter Hydrothermalbedingungen bilden trilakunare Keggin-{B-, -PW9O34}-Fragmente und Nickelionen die beiden größten Ni-substituierten Poly(polyoxowolframate) mit der größten Zahl an Ni-Ionen in einem bekannten Polyoxometallat. Aminliganden verbrücken die Nanocluster der Fragmente zur 1D-Struktur der Polyoxometallate (siehe Struktur; rote Oktaeder WO6, gelbe Tetraeder PO4, grün,Ni, rot,O, blau,N, grau,C). [source] A Ladder-like One-dimensional Chain Based on a New Biradical and CuII: Crystal Structure and Magnetic Properties,CHINESE JOURNAL OF CHEMISTRY, Issue 9 2010Chao Wang Abstract A new biradical di(4-(1,-oxyl-3,-oxido-4,,4,,5,,5,-tetramethyl-4,,5,-dihydro-1,H -imidazol-2,-yl)phenyl) ether (1) and its copper complex 2 were synthesized and characterized structurally. The X-ray structure determination revealed that, the complex is in the triclinic P -1 space group and displays a ladder-like structure. Each copper atom is surrounded by four oxygen atoms from hexafluoroacetylacetone and two oxygen atoms from biradical. The magnetic measurements show that biradical 1 exhibits a weak intramolecular nitroxide-nitroxide antiferromagnetic coupling and copper complex 2 possesses weak ferromagnetic coupling (J=5.09 cm,1) between CuII and radical, which attributed to interaction between copper spin and the axially coordinated nitronyl nitroxide spin. [source] Novel Cadmium(II) Adipate Coordination Polymers with Structural Transformation via Oxalate Ligand: Syntheses, Structures and Fluorescence PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2004Na Hao Abstract Two novel cadmium adipate coordination polymers [Cd{O2C(CH2)4CO2}{1,10-phen}]n (1) and [Cd2(C2O4){O2C(CH2)4CO2(OH2)2}{2,2,-bipy}]·H2O (2) [adipic acid = HO2C(CH2)4CO2H] have been hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. Crystallographic data for 1: monoclinic, C2/c, a = 16.186(3) Å, b = 15.487(3) Å, c = 14.052(3) Å, , = 112.73(3)°, Z = 8. Crystal data for 2: monoclinic, Cc, a = 23.448(5) Å, b = 11.826(2) Å, c = 8.3163(17) Å, , = 99.08(3)°, Z = 4. The structural analysis reveals that 1 forms a novel one-dimensional chain in which the binuclear Cd centers are linked by adipate anions. Compound 2 is the first example in which both a 2,2,-bipy ligand and an oxalate group are found in the {M/adipate} system. Compound 2 possesses one-dimensional sine- or cosine-type chains, which are alternately connected together by the oxalate group to form a three-dimensional framework. The structural determination reveals that the introduction of the oxalate ligand causes the dimensional transformation of the compounds. Compounds 1 and 2 show strong fluorescent properties at room temperature. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Lattice modes in a system of charge rotators in a plasma environmentPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2004S. V. Vladimirov Abstract Three dimensional rotatory modes of oscillations in a one-dimensional chain of rod-like charged particles or dust grains in a plasma are investigated. An oscillatory dependence on wavenumber and a critical dependence on the relative strengths of the confining potential is found. The characteristic frequency range for the oscillatory modes is of the order of the dust plasma frequency. The azimuthal and colatitudinal modes show opposite characteristics in the near and far interparticle distance regimes, respectively. The rods are shown to move, or switch to the relevant equilibrium, dependind on the confining parameters. This is an example of a phase change phenomenon which is analogous to that observed in liquid crystals. The ability to line up rods in different directions, by alternating the relative sizes of the confining potentials, is a powerful tool for applications. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Polymorphism in the nitrate salt of the [Mn(acetylacetonate)2(H2O)2]+ ionACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2010A. R. Biju The crystallization of [Mn(acac)2(H2O)2]+ from solutions containing excess nitrate leads to the formation of four polymorphs. All polymorphs contain two different types of complex ions, one containing essentially coplanar acac ligands and the other in which the two acac ligands together assume a chair conformation. Molecular modelling using DFT (density-functional theory) calculations shows that the coplanar conformation is the electronically stable one. The hydrogen bonding between the trans -water molecules and the nitrate ion produces a one-dimensional chain of 12-membered rings, which are further organized into a two-dimensional network via a lattice water molecule. Lattice-energy calculations have been carried out to compare the stabilities of the four polymorphs. [source] New organically templated vanadium tellurites: (H2pn)[V2TeO8] (pn is propane-1,3-diamine)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009Xihe Huang The title compound, poly[propane-1,3-diaminium hexa-,-oxido-dioxidotellurium(IV)divanadium(V)], (C3H12N2)[V2O8Te] or (H2pn)[V2TeO8] (pn is propane-1,3-diamine), contains a two-dimensional anionic layer and the diprotonated pn cation for charge compensation. The anionic layer consists of pyrovanadates and [TeO3] pyramids, which are linked alternately through corner-sharing to form a one-dimensional chain. These one-dimensional chains are crosslinked through two weak Te,O bonds, constructing an anionic layer. Hydrogen bonds are observed involving the diprotonated pn cation and the O atoms of the anionic framework. [source] Nickel and zinc complexes with a monodentate heterocycle and tridentate Schiff base ligands: self-assembly to one- and two-dimensional supramolecular networks via hydrogen bondingACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2009Xiao-Hua Chen In the complex (morpholine)[2-hydroxy- N,-(5-nitro-2-oxidobenzylidene)benzohydrazidato]nickel(II), [Ni(C14H9N3O5)(C4H9NO)], (I), the NiII center is in a square-planar N2O2 coordination geometry. The complex bis[,-2-hydroxy- N,-(2-oxidobenzylidene)benzohydrazidato]bis[(morpholine)zinc(II)], [Zn2(C14H10N2O3)2(C4H9NO)2], (II), consists of a neutral centrosymmetric dimer with a coplanar Zn2(,2 -O)2 core. The two ZnII centers are bridged by phenolate O atoms. Each ZnII center exhibits a distorted square-pyramidal stereochemistry, in which the four in-plane donors come from the O,N,O,-tridentate 2-hydroxy- N,-(2-oxidobenzylidene)benzohydrazidate(2,) ligand and a symmetry-related phenolate O atom, and the axial position is coordinated to the N atom from the morpholine molecule. There are intramolecular phenol,hydrazide O,H...N hydrogen bonds present in both (I) and (II). In (I), square-planar nickel complexes are linked by intermolecular morpholine,morpholine N,H...O hydrogen bonds, leading to a one-dimensional chain, while in (II) an infinite two-dimensional network is formed via intermolecular hydrogen bonds between the coordinated morpholine NH groups and the uncoordinated phenolate O atoms. [source] catena -Poly[[[pyridinecopper(II)]bis[,3 -4-(2-oxidobenzylideneamino)benzoato]] dimethylformamide disolvate], a polymer composed of dimeric dicopper building unitsACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2007Qing-Ling Ni The title compound, {[Cu(C14H9NO3)(C5H5N)]·C3H7NO}n or {[Cu2L2(py)2]·2DMF}n [py is pyridine, L is 4-(salicylideneamino)benzoate and DMF is dimethylformamide], is composed of dimeric dicopper [CuL(py)]2 building units, which are interlinked into a one-dimensional chain through the formation of Cu,OCOO bonds. The dimeric unit is centrosymmetric, containing two CuII atoms linked by bridging phenolate O atoms into a Cu2O2 plane with a chelating Cu,O bond length of 1.927,(2),Å and a bridging Cu,O bond length of 2.440,(2),Å. Interchain C,H...O and ,,, stacking interactions are responsible for an extensive three-dimensional structure in which the resulting channels are filled by DMF solvent molecules. [source] Synthesis, Crystal Structures, and Properties of Oxovanadium(IV),Lanthanide(III) Heteronuclear ComplexesCHEMISTRY - A EUROPEAN JOURNAL, Issue 17 2005Wei Shi Abstract A new series of oxovanadium(IV),lanthanide(III) heteronuclear complexes [Yb(H2O)8]2[(VO)2(TTHA)]3,21,H2O (1), {[Ho(H2O)7(VO)2(TTHA)][(VO)2(TTHA)]0.5}, 8.5,H2O (2), {[Gd(H2O)7(VO)2(TTHA)][(VO)2(TTHA)]0.5},8.5,H2O (3), {[Eu(H2O)7][(VO)2(TTHA)]1.5}, 10.5,H2O (4), and [Pr2(H2O)6(SO4)2][(VO)2(TTHA)] (5) (H6TTHA=triethylenetetraaminehexaacetic acid) were prepared by using the bulky flexible organic acid H6TTHA as structure-directing agent. X-ray crystallographic studies reveal that they contain the same [(VO)2(TTHA)]2, unit as building block, but the Ln3+ ion lies in different coordination environments. Although the lanthanide ions always exhibit similar chemical behavior, the structures of the complexes are not homologous. Compound 1 is composed of a [Yb(H2O)8]3+ ion and a [(VO)2(TTHA)]2, ion. Compounds 2 and 3 are isomorphous; both contain a trinuclear [Ln(H2O)7(VO)2(TTHA)]+ (Ln=Ho for 2 and Gd for 3) ion and a [(VO)2(TTHA)]2, ion. Compound 4 is an extended one-dimensional chain, in which each Eu3+ ion links two [(VO)2(TTHA)]2, ions. For 5, the structure is further assembled into a three-dimensional network with an interesting framework topology comprising V2Pr2 and V4Pr2 heterometallic lattices. Moreover, 4 and 5 are the first oxovanadium(IV),lanthanide(III) coordination polymers and thus enlarge the realm of 3d,4f complexes. The IR, UV/Vis, and EPR spectra and the magnetic properties of the heterometallic complexes were studied. Notably, 2 shows unusual ferromagnetic interactions between the VO2+ and Ho3+ ions. [source] Luminescent Property of a Supramolecular Silver(I)-Thiolate Complex Based on Secondary Ag-S Interactions and Hydrogen BondsCHINESE JOURNAL OF CHEMISTRY, Issue 9 2001Wei-Ping Su Abstract The supramolecular silver(I)-thiolate complex [Ag(,2 -SC4N2H4)2(SCN)]n has been prepared from the reaction of AgSCN and pyrimidine-2-thiol in DMF. X-ray diffraction analysis shows that the supramolecular structure exhibits one-dimensional chain through the secondary Ag-S interactions and the chains are further linked by strong hydrogen bonds to form a three dimensional network. The luminescence effect from the silver-centered state of S,Ag LMCT in solid state is different from that in solution due to the secondary Ag-S interactions. [source] 1-D-Tin(II) Phenylchalcogenolato Complexes ,1[Sn(EPh)2] (E = S, Se, Te) , Synthesis, Structures, Quantum Chemical Studies and Thermal BehaviourEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 3 2010Andreas Eichhöfer Abstract A series of three 1-D-tin(II) phenylchalcogenolato complexes ,1[Sn(EPh)2] (E = S, Se, Te) were synthesized in yields > 80,% by reaction of SnCl2 with two equivalents of PhESiMe3 in organic solvents. In the crystal the molecules form two different types of one-dimensional chains. In ,1[Sn(SPh)2] the tin atoms are distorted trigonal pyramidal coordinated by sulfur atoms (two bonds within a monomer and one longer bond between neighbored monomers), while in ,1[Sn(EPh)2] (E = Se, Te) the tin atoms show contacts to two neighbored monomers leading to a fourfold coordination of the tin atoms by either selenium or tellurium atoms. The bond situation is discussed on the basis of density functional calculations. Thermal treatment mostly leads to the formation of the corresponding phase pure tin(II) chalcogenides however sublimation plays an increasing role ongoing from the tellurolato to the thiolato complex especially for the use of vacuum conditions. The investigation of the volatile cleavage products reveals the occurence of more complex reactions in the gas phase than the formal stoichiometric cleavage of EPh2 (E = S, Se, Te) with formation of SnE. [source] Synthesis, Structure and Magnetic Behaviour of Manganese(II) Selenolate Complexes ,1[Mn(SePh)2], [Mn(SePh)2(bipy)2] and [Mn(SePh)2(phen)2] (bipy = bipyridyl, phen = phenanthroline)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 30 2007Andreas Eichhöfer Abstract The manganese selenolate complex ,1[Mn(SePh)2] has been prepared by reaction of Mn(OOCCH3)2 with 2 equiv.PhSeSiMe3 in thf. In the crystal structure, the compound forms one-dimensional chains, and the bridging selenolate ligands result in relatively short metal,metal contacts of about 3 Å. Reaction with two equivalents of the Lewis bases 2,2,-bipyridine and 1,10-phenanthroline yielded the monomeric octahedral complexes [Mn(SePh)2(2,2,-bipy)2] and [Mn(SePh)2(1,10-phen)2], respectively. The magnetic and optical properties of these complexes have been investigated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] One-Dimensional Oxalato-Bridged Metal(II) Complexes with 4 - Amino-1,2,4-triazole as Apical LigandEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 21 2005Urko García-Couceiro Abstract The synthesis, chemical characterization, thermal behavior and magnetic properties of six new one-dimensional oxalato-bridged metal(II) complexes of formula [M(,-ox)(4atr)2]n [MII = Cu (1), Ni (2), Co (3), Zn (4), Fe(5)] and [Cd(,-ox)(4atr)2(H2O)]n (6) (ox = oxalato dianion, 4atr = 4-amino-1,2,4-triazole) are reported. The crystal structures of 1 and 6 have been solved by single-crystal X-ray diffraction, whereas the remaining compounds have been studied by means of X-ray powder diffraction methods. Compounds 1,5 are isomorphous and crystallize in the triclinic space group P1¯ with unit cell parameters for 1 of a = 5.538(1) Å, b = 7.663(1) Å, c = 7.711(2) Å, , = 62.21(1)°, , = 73.91(1)°, , = 86.11(1)°, and Z = 1. The crystal structures are comprised of one-dimensional linear chains in which the trans -[M(4atr)2]2+ units are sequentially bridged by bis(bidentate) oxalato ligands, resulting in an octahedral O4N2 donor set. Cryomagnetic susceptibility measurements show the occurrence of antiferromagnetic intrachain interactions for 2, 3, and 5, whereas compound 1 exhibits a weak ferromagnetic coupling in agreement with the out-of-plane exchange pathway involved. The magnetic behavior of 1 and 2 is analyzed and discussed in the light of the available magneto-structural data for analogous systems. CdII complex crystallizes in the monoclinic space group C2/c with unit cell parameters of a = 16.128(2) Å, b = 6.757(1) Å, c = 11.580(2) Å, , = 104.46(1)°, and Z = 4. Its crystal structure contains one-dimensional chains in which metal centers are heptacoodinated to four oxygen atoms from two symmetry-related bis(bidentate) oxalato bridges, two endocyclic nitrogen atoms of trans -coordinated triazole ligands and one water molecule, to give a CdO4OwN2 pentagonal-bipyramidal geometry. Thermoanalytical and variable-temperature X-ray powder diffraction analyzes show that compound 6 undergoes a reversible dehydration,hydration process in which the anhydrous residue crystallizes with a different crystal lattice retaining the dimensionality of the oxalato,metal framework. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] A Novel 3-D Self-Penetrating Topological Network Assembled by Mixed Bridging LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2004Xing Li Abstract The assembly of 5-sulfoisophthalic acid (H3sipa) and 4,4,-bipyridine (bpy) with Cd2+ ions gave rise to a new polymeric complex {[Cd3(sipa)2(bpy)4(H2O)2]·3H2O}n (1). X-ray diffraction analysis reveals that complex 1 has a 3-D self-penetrating network formed by the interlocking and interweaving of two types of one-dimensional chains comprising two kinds of Cd4(sipa)4 and Cd4(bpy)4 units, respectively. The sipa3, ligand serves as the connector and the Cd2+ ion as the node. Thermogravimetric analysis (TGA) and the luminescence property of 1 are discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Synthesis and Microstructural Characterisation of Two New One-Dimensional Members of the (A3NiMnO6),(A3Mn3O9), Homologous Series (A = Ba, Sr)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2003María Hernando Abstract Two new members of the one-dimensional (A3NiMnO6),(A3Mn3O9), homologous series, with the compositions (Sr0.75Ba0.25)5NiMn3O12 and Sr9Ni2Mn5O21, have been synthesised. Their structures can each be described as a hexagonal array of infinite one-dimensional chains of face-sharing polyhedra, running parallel to the c axis and separated by the Sr/Ba cations. The structure of (Sr0.75Ba0.25)5NiMn3O12, which constitutes the (, = 3, , = 2) member of the series, is made up of three face-sharing octahedra linked by one trigonal prism. For Sr9Ni2Mn5O21 (, = 2, , = 1) the sequence of polyhedra along the chains corresponds to a motif consisting of two octahedra,one trigonal prism,three octahedra,one trigonal prism. The manganese atoms occupy the octahedral sites in both phases, while the Ni2+ cations are distributed in the trigonal-prismatic sites in a disordered way. Only a small fraction of these (close to 20%) is located at the centres of the trigonal prisms, 80% being displaced towards the rectangular faces of the polyhedra and giving rise to a square-planar-like coordination. Both oxides present twinned microstructures, as evidenced by SAED and HREM. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Structural characterization of anhydrous naloxone- and naltrexone hydrochloride by high resolution laboratory X-ray powder diffraction and thermal analysisJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 12 2007Kunihisa Sugimoto Abstract The crystal structures of the analgesic compounds anhydrous naloxone and naltrexone hydrochloride were determined ab initio from high resolution laboratory X-ray powder diffraction data. Both compounds crystallize in the orthorhombic space group P212121 with lattice parameters of a,=,14.6588(10) Å, b,=,17.4363(9) Å, c,=,7.96200(22) Å, and V,=,2035.06(23) Å3 for naloxone hydrochloride and a,=,15.4560(5) Å, b,=,14.9809(4) Å, c,=,7.84121(18) Å, and V,=,1815.58(11) Å3 for naltrexone hydrochloride. The crystal structure of anhydrous naloxone hydrochloride forms one-dimensional chains through hydrogen bonds. In the crystal structure of anhydrous naltrexone hydrochloride, two-dimensional sheets are formed by hydrogen bonds. The dehydration processes of naloxone hydrochloride dehydrate and naltrexone hydrochloride tetrahydrate was analyzed by DTA, DSC, TG, and MG. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 96: 3316,3323, 2007 [source] Polymorphism and piezochromicity in the three-dimensional network-based phosphate RbCuPO4ACTA CRYSTALLOGRAPHICA SECTION B, Issue 4 2010Paul F. Henry Rubidium copper phosphate, RbCuPO4, forms two room-temperature polymorphs that have been investigated with neutron powder diffraction. Polymorph (II) can be converted quantitatively into (I) by grinding the material or by pelletization, and the phase transition is accompanied by a significant colour change from very pale green to sky blue. Polymorph (II) can be obtained essentially free of (I) by quenching from 723,K. Each polymorph shows two unique Cu atoms: in (I) both sites are four-coordinate in a 2:1 ratio, whereas in (II) the atoms are four- and five-coordinate in a 1:1 ratio. In each case these sites are linked by phosphate tetrahedra to form three-dimensional frameworks based on the 42638- a four-connected net. The Rb atoms are hosted in the six- and eight-ring channels that are similar to those observed in zeolite ABW. The (II) , (I) phase transition is also accompanied by a volume reduction of 2.1% even though the average coordination of the Cu atoms also falls. The structures of the polymorphs are critically examined and compared with those of KNiPO4 and KCuPO4 in terms of hexagonal close packing containing ordered phosphate arrays. As a result of buckling of the six-ring layers, one-dimensional chains of dimerized copper polyhedra are identified in (II), chains that become trimers with mirror symmetry in (I). [source] Mullite-type Ga4B2O9: structure and order,disorder phenomenonACTA CRYSTALLOGRAPHICA SECTION B, Issue 2 2010Rihong Cong Ga4B2O9, an aluminium-free mullite-type compound, was prepared by a boric-acid flux method and its structure was determined using powder X-ray diffraction techniques, in combination with transmission electron microscopy, solid-state 11B MAS-NMR and IR spectroscopies. GaO6 octahedra share edges in a trans -manner forming one-dimensional chains along the b direction, and the chains are further cross-linked by GaO5, BO3 and BO4 groups into a three-dimensional mullite-type structure. The disorder of the inter-chain groups results in a small unit cell for Ga4B2O9 compared with that for Al4B2O9, an ordered compound with a superstructure. By deconstructing the structure of Ga4B2O9, we were able to identify the fundamental building units and their linking rules which can be used to reconstruct the ordered and disordered structures. For Ga4B2O9, we found that the structure is intrinsically disordered within the ac plane, but ordered along the b axis. The three-dimensional structure can then be constructed by stacking the disordered ac sheets along the b axis (½b) with a ½a shift. The fundamental building units and exclusivity rules identified in this gallium borate mullite may also be useful for understanding other related mullite phases. The structure analysis applying the proposed method is used to recognize the structural features of Al4B2O9 and Al18B4O33. [source] Powder X-ray studies of meso -hexamethyl propylene amine oxime (meso -HMPAO) in two different phasesACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2010Mahmoud Al-Ktaifani Two different forms of meso -3,3,-[2,2-dimethylpropane-1,3-diylbis(azanediyl)]dibutan-2-one dioxime, commonly called meso -hexamethyl propylene amine oxime (HMPAO), C13H28N4O2, designated , and ,, were isolated by fractional crystallization and their crystal structures were determined by powder X-ray diffraction using the direct-space method with the parallel tempering algorithm. The , form was first crystallized from acetonitrile solution, while the , form was obtained by recrystallization of the , phase from diethyl ether. The , form crystallizes in the triclinic system (space group P), with one molecule in the asymmetric unit, while the crystal of the , form is monoclinic (space group P21/n), with one molecule in the asymmetric unit. In both phases, the molecules have similar conformations and RS/EE geometric isomerism. The crystal packing of the two phases is dominated by intermolecular hydrogen-bonding interactions between the two O,H oxime groups of an individual molecule and the amine N atoms of two different adjacent molecules, which lead to segregation of extended poly(meso -HMPAO) one-dimensional chains along the c direction. The structures of the two phases are primarily different due to the different orientations of the molecules in the chains. [source] A new adamantanecarboxylate coordination polymer: poly[[(,3 -adamantane-1,3-dicarboxylato)aquadioxidouranium(VI)] monohydrate]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010Julia A. Rusanova The title compound, {[U(C12H14O4)O2(H2O)]·H2O}n, is the first actinide complex featuring adamantanecarboxylate ligands. The metal ion possesses a pentagonal,bipyramidal UO7 coordination involving two axial oxide ligands [U,O = 1.732,(5) and 1.764,(5),Å] and five equatorial O atoms [U,O = 2.259,(5),2.494,(4),Å] of aqua and carboxylate ligands. The latter display pseudo-chelating and bridging coordination modes of the carboxylate groups that are responsible for the generation of the centrosymmetric discrete uranium,carboxylate [UO2(,- RCOO)2UO2] dimers [U...U = 5.5130,(5),Å] and their connection into one-dimensional chains. Hydrogen bonding involving two coordinated and two solvent water molecules [O...O = 2.719,(7),2.872,(7),Å] yields centrosymmetric (H2O)4 ensembles and provides noncovalent linkage between the coordination chains to generate a three-dimensional network structure. [source] Cocrystals of 2,3,5,6-tetrafluorobenzene-1,4-diol with diaza aromatic compoundsACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Agnieszka Czapik 2,3,5,6-Tetrafluorobenzene-1,4-diol easily forms cocrystals with heteroaromatic bases containing the pyrazine unit. In the 1:1 complexes with pyrazine, C6H2F4O2·C4H4N2, (I), and quinoxaline, C6H2F4O2·C8H6N2, (II), the crystal components are linked via O,H...N hydrogen bonds into one-dimensional chains. With the largest base, phenazine, the 1:2 benzenediol,phenazine complex, C6H2F4O2·2C12H8N2, (III), was obtained, with the molecules linked via O,H...N interactions into a discrete heterotrimer. In all three cocrystals, the two types of molecules are organized into layers via softer C,H...O and C,H...F interactions and ,,, stacking interactions, with stronger hydrogen bonds linking molecules of adjacent layers. In (II) and (III), molecules are arranged into heterostacks, whereas in (I) separate stacks are formed by the heterocyclic base and the benzenediol molecule. [source] N,N,-Diethyl-4-nitrobenzene-1,3-diamine, 2,6-bis(ethylamino)-3-nitrobenzonitrile and bis(4-ethylamino-3-nitrophenyl) sulfoneACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Thomas J. Payne N,N,-Diethyl-4-nitrobenzene-1,3-diamine, C10H15N3O2, (I), crystallizes with two independent molecules in the asymmetric unit, both of which are nearly planar. The molecules differ in the conformation of the ethylamine group trans to the nitro group. Both molecules contain intramolecular N,H...O hydrogen bonds between the adjacent amine and nitro groups and are linked into one-dimensional chains by intermolecular N,H...O hydrogen bonds. The chains are organized in layers parallel to (101) with separations of ca 3.4,Å between adjacent sheets. The packing is quite different from what was observed in isomeric 1,3-bis(ethylamino)-2-nitrobenzene. 2,6-Bis(ethylamino)-3-nitrobenzonitrile, C11H14N4O2, (II), differs from (I) only in the presence of the nitrile functionality between the two ethylamine groups. Compound (II) crystallizes with one unique molecule in the asymmetric unit. In contrast with (I), one of the ethylamine groups, which is disordered over two sites with occupancies of 0.75 and 0.25, is positioned so that the methyl group is directed out of the plane of the ring by approximately 85°. This ethylamine group forms an intramolecular N,H...O hydrogen bond with the adjacent nitro group. The packing in (II) is very different from that in (I). Molecules of (II) are linked by both intermolecular amine,nitro N,H...O and amine,nitrile N,H...N hydrogen bonds into a two-dimensional network in the (10) plane. Alternating molecules are approximately orthogonal to one another, indicating that ,,, interactions are not a significant factor in the packing. Bis(4-ethylamino-3-nitrophenyl) sulfone, C16H18N4O6S, (III), contains the same ortho nitro/ethylamine pairing as in (I), with the position para to the nitro group occupied by the sulfone instead of a second ethylamine group. Each 4-ethylamino-3-nitrobenzene moiety is nearly planar and contains the typical intramolecular N,H...O hydrogen bond. Due to the tetrahedral geometry about the S atom, the molecules of (III) adopt an overall V shape. There are no intermolecular amine,nitro hydrogen bonds. Rather, each amine H atom has a long (H...O ca 2.8,Å) interaction with one of the sulfone O atoms. Molecules of (III) are thus linked by amine,sulfone N,H...O hydrogen bonds into zigzag double chains running along [001]. Taken together, these structures demonstrate that small changes in the functionalization of ethylamine,nitroarenes cause significant differences in the intermolecular interactions and packing. [source] A third polymorph of 4-(2,6-difluorophenyl)-1,2,3,5-dithiadiazolylACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2010Elisabeth M. Fatila The crystal structure of a third polymorphic form of the known 4-(2,6-difluorophenyl)-1,2,3,5-dithiadiazolyl radical, C7H3F2N2S2, is reported. This new polymorph represents a unique crystal-packing motif never before observed for 1,2,3,5-dithiadiazolyl (DTDA) radicals. In the two known polymorphic forms of the title compound, all of the molecules form cis -cofacial dimers, such that two molecules are ,-stacked with like atoms one on top of the other, a common arrangement for DTDA species. By contrast, the third polymorph, reported herein, contains two crystallographically unique molecules organized such that only 50% are dimerized, while the other 50% remain monomeric radicals. The dimerized molecules are arranged in the trans -antarafacial mode. This less common dimer motif for DTDA species is characterized by ,,, interactions between the S atoms [S...S = 3.208,(1),Å at 110,K], such that the two molecules of the dimer are related by a centre of inversion. The most remarkable aspect of this third polymorph is that the DTDA dimers are co-packed with monomers. The monomeric radicals are arranged in one-dimensional chains directed by close lateral intermolecular contacts between the two S atoms of one DTDA heterocycle and an N atom of a neighbouring coplanar DTDA heterocycle [S...N = 2.857,(2) and 3.147,(2),Å at 110,K]. [source] Di-,-acesulfamato-,3N,O:O;,3O:N,O -bis[(acesulfamato-,2N,O)bis(3-methylpyridine)cadmium(II)]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2009Zarife Sibel In the structure of the title compound, [Cd2(C4H4NO4S)2(C6H7N)2], the dinuclear CdII complex is located on a twofold axis with two Cd2+ ions bridged by two oxide O atoms. Each Cd2+ ion is additionally coordinated in an equatorial plane by two N and three O atoms of the acesulfamate ligands and axially by two N atoms of the 3-methylpyridine ligands, resulting in a distorted pentagonal bipyramidal coordination. We present here an example of a supramolecular assembly based on hydrogen bonds in a mixed-ligand metal complex; intermolecular C,H...O hydrogen bonds give rise to R44(40) rings, which lead to one-dimensional chains. [source] 1:1 Adducts of 2,2,-[isopropylidenebis(p -phenyleneoxy)]diacetic acid with dimethylammonium and 4,4,-bipyridineACTA CRYSTALLOGRAPHICA SECTION C, Issue 11 2009Ze-Bao Zheng The title compounds, dimethylammonium 2-{4-[1-(4-carboxymethoxyphenyl)-1-methylethyl]phenoxy}acetate, C2H8N+·C19H19O6,, (I), and 2,2,-[isopropylidenebis(p -phenyleneoxy)]diacetic acid,4,4,-bipyridine (1/1), C19H20O6·C10H8N2, (II), are 1:1 adducts of 2,2,-[isopropylidenebis(p -phenyleneoxy)]diacetic acid (H2L) with dimethylammonium or 4,4,-bipyridine. The component ions in (I) are linked by N,H...O, O,H...O and C,H...O hydrogen bonds into continuous two-dimensional layers parallel to the (001) plane. Adjacent layers are stacked via C,H...O hydrogen bonds into a three-dimensional network with an ,ABAB, alternation of the two-dimensional layers. In (II), two H2L molecules, one bipy molecule and two half bipy molecules are linked by O,H...N hydrogen bonds into one-dimensional chains and rectanglar-shaped rings. They are assembled via,,, stacking interactions and C,H...O hydrogen bonds into an intriguing zero-dimensional plus one-dimensional poly(pseudo)rotaxane motif. [source] New organically templated vanadium tellurites: (H2pn)[V2TeO8] (pn is propane-1,3-diamine)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009Xihe Huang The title compound, poly[propane-1,3-diaminium hexa-,-oxido-dioxidotellurium(IV)divanadium(V)], (C3H12N2)[V2O8Te] or (H2pn)[V2TeO8] (pn is propane-1,3-diamine), contains a two-dimensional anionic layer and the diprotonated pn cation for charge compensation. The anionic layer consists of pyrovanadates and [TeO3] pyramids, which are linked alternately through corner-sharing to form a one-dimensional chain. These one-dimensional chains are crosslinked through two weak Te,O bonds, constructing an anionic layer. Hydrogen bonds are observed involving the diprotonated pn cation and the O atoms of the anionic framework. [source] Hydrogen-bonded network in the trichloroacetate salts of 2-amino-5-chloropyridinium and 2-methyl-5-nitroanilinium monohydrateACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2009Jan Janczak In the crystal structures of 2-amino-5-chloropyridinium trichloroacetate, C5H6ClN2+·C2Cl3O2,, (I), and 2-methyl-5-nitroanilinium trichloroacetate monohydrate, C7H9N2O2+·C2Cl3O2,·H2O, (II), the protonated planar 2-amino-5-chloropyridinium [in (I)] and 2-methyl-5-nitroanilinium [in (II)] cations interact with the oppositely charged trichloroacetate anions to form hydrogen-bonded one-dimensional chains in (I) and, together with water molecules, a three-dimensional network in (II). The crystals of (I) exhibit nonlinear optical properties. The second harmonic generation efficiency in relation to potassium dihydrogen phosphate is 0.77. This work demonstrates the usefulness of trichloroacetic acid in crystal engineering for obtaining new materials for nonlinear optics. [source] A structural systematic study of four isomers of difluoro- N -(3-pyridyl)benzamideACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2009Joyce McMahon The four isomers 2,4-, (I), 2,5-, (II), 3,4-, (III), and 3,5-difluoro- N -(3-pyridyl)benzamide, (IV), all with formula C12H8F2N2O, display molecular similarity, with interplanar angles between the C6/C5N rings ranging from 2.94,(11)° in (IV) to 4.48,(18)° in (I), although the amide group is twisted from either plane by 18.0,(2),27.3,(3)°. Compounds (I) and (II) are isostructural but are not isomorphous. Intermolecular N,H...O=C interactions form one-dimensional C(4) chains along [010]. The only other significant interaction is C,H...F. The pyridyl (py) N atom does not participate in hydrogen bonding; the closest H...Npy contact is 2.71,Å in (I) and 2.69,Å in (II). Packing of pairs of one-dimensional chains in a herring-bone fashion occurs via,-stacking interactions. Compounds (III) and (IV) are essentially isomorphous (their a and b unit-cell lengths differ by 9%, due mainly to 3,4-F2 and 3,5-F2 substitution patterns in the arene ring) and are quasi-isostructural. In (III), benzene rotational disorder is present, with the meta F atom occupying both 3- and 5-F positions with site occupancies of 0.809,(4) and 0.191,(4), respectively. The N,H...Npy intermolecular interactions dominate as C(5) chains in tandem with C,H...Npy interactions. C,H...O=C interactions form R22(8) rings about inversion centres, and there are ,,, stacks about inversion centres, all combining to form a three-dimensional network. By contrast, (IV) has no strong hydrogen bonds; the N,H...Npy interaction is 0.3,Å longer than in (III). The carbonyl O atom participates only in weak interactions and is surrounded in a square-pyramidal contact geometry with two intramolecular and three intermolecular C,H...O=C interactions. Compounds (III) and (IV) are interesting examples of two isomers with similar unit-cell parameters and gross packing but which display quite different intermolecular interactions at the primary level due to subtle packing differences at the atom/group/ring level arising from differences in the peripheral ring-substitution patterns. [source] | ||||||||||||||||||||||