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1.
A mixed-ligand Zn(II) complex formulated as [Zn(aldtc)2(bipy)] (aldtc=diallyldithiocarbamate; bipy=2,2′-bipyridine) was synthesized and characterized by IR, 1H and 13C NMR spectral measurements and X-ray crystallography. The crystal structure of this complex indicates that Zn has a distorted octahedral geometry. The Zn—N distances are invariant (2.168(2) Å), while those of the Zn—S are slightly different (2.5408(9) and 2.5440(9) Å). The N—Zn—N, S—Zn—S and N—Zn—S bond angles are in the range 75.35(13)–99.75(7)°, 70.48(3)–161.02(5)° and 95.26(7)–160.32(7)°, respectively. The crystal packing of the complex shows different motifs of supramolecularity resulting from both hydrophilic ((π)C—H···S) and hydrophobic ((allyl)C—H···C(π)) intermolecular interactions. These interactions result in a chain arrangement of molecules along crystallographic c axis and the chains are further connected via π···π stacking along with ((π)C—H···S along b axis leading to an overall crystal packing that can be regarded as layers of complexes along bc plane, which are held together through nonconventional hydrogen bonding and π···π stacking.  相似文献   
2.
N+–H?Br–M and (π)C–H?Br–M hydrogen bond synthons have been exploited in the crystallization of a series of 2,2′-iminodipyridinium(2+) dication (hereafter 2,2′-imdipyH2), (C10H11N3)[MX4] salts (M = Co and Hg; X = Cl and Br) and 2,2′-iminodipyridinium(1+) cation (hereafter 2,2′-imdipyH), (C10H10N3)2[MX4] salts (M = Co, Hg; X = Cl and Br). Intermolecular interactions and crystal supramolecularity adopted in these structures were analyzed and compared with reported similar structures, (C10H11N3)[CuCl4] and (C10H10N3)2[CoCl4]. In these salts only one structural form for the halometallate species is observed namely mononuclear tetrahedral. The crystal supramolecularity in the (2,2′-imdipyH2)[MX4] series corresponds to three distinct structural motifs: Parallel ribbons of infinitely connected cyclic dimers of two dications and two anions found in the isomorphous salts of [CoCl4]2? and [CuCl4]2?; and cyclic dimer hearing-bone packing motif found in the isomorphous dication salts of [CoBr4]2? and [HgBr4]2?. Infinitely helical layers based on alternating ?anion?two stacked cations ?anion? two stacked cations? are found in the isomorphous salts of (2,2′-imdipyH)2[CoCl4] and (2,2′-imdipyH)2[HgBr4].  相似文献   
3.
In the structural motifs of two isomorphous triclinic salts, (C5H6Br2N3)2[MBr4] (M = CdII and MnII), each [MBr4]2− anion interacts with eight surrounding 2,6‐diamino‐3,5‐dibromopyridinium cations through intermolecular C/N—H...Br and Br...Br interactions, leading to a three‐dimensional framework structure. The cations show a minor degree of π–π stacking, adding extra stability to the three‐dimensional architecture.  相似文献   
4.
The structures of three isomorphous compounds, namely bis(2,6‐dibromopyridinium) tetrabromidocuprate(II) dihydrate, (C5H4Br2N)2[CuBr4]·2H2O, bis(2,6‐dibromopyridinium) tetrabromidocadmate(II) dihydrate, (C5H4Br2N)2[CdBr4]·2H2O, and bis(2,6‐dibromopyridinium) tetrabromidomercurate(II) dihydrate, (C5H4Br2N)2[HgBr4]·2H2O, show a crystal supramolecularity represented by M—Br...H—O—H...Br—M intermolecular interactions along with (π)N—H...OH2 hydrogen‐bonding interactions forming layers connected via aryl–aryl face‐to‐face stacking of cations, leading to a three‐dimensional network. The anions have significantly distorted tetrahedral geometry and crystallographic C2 symmetry. The stability of this crystal lattice is evidenced by the crystallization of a whole series of isomorphous compounds.  相似文献   
5.
The title compound, cis-[Rh(biq)2Cl2]Cl·3H2O (biq = 2,2′-biquinoline) crystallized in the monoclinic space group P2 1 /n with a = 11.231(2) Å, b = 20.895(4) Å, c = 14.081(3) Å, β = 94.76(3)°, V = 3293.0(11) Å3, D c = 1.565 g cm−3, μ = 0.806 mm−1, F(000) = 1576 and Z = 4. It contains a monomeric [Rh(biq)2Cl2]+ cation, a chloride ion and three molecules of H2O. The rhodium(III) ion is hexa coordinated forming a distorted octahedral arrangement. The mean Rh(III)–N distance for the four Rh(III)–N bonds is 2.0625 Å. The two chloride atoms are bonded in a cis configuration [Rh(III)–Cl bond distances are 2.329(3) and 2.341(4) Å]. The structure shows a curling stacks of cationic complexes interacting via offset-face-to-face (OFF) π–π aryl interaction motif. Water molecules and chloride ions are hydrogen bonded (H2O···H–OH and Cl···H–OH) and links the curling stacks by hydrogen bonding via Rh–Cl···H–OH interactions.  相似文献   
6.
Abstract A single crystal structure determination of the complex (4,4′-bipyridinium)[CdBr4] n , [henceforth (I)], has been carried out. It crystallizes in the monoclinic space group C2/c, with the following cell parameters: a = 16.119(3) ?, b = 13.206(3) ?, c = 7.2601(15) ?, β = 115.62°, V = 1393.5(6) ?3, with Z = 4 formula units. The polymeric anion forms an infinite zig-zag chain of edge-sharing octahedra along c, with a distorted octahedral stereochemistry around Cd. There are N–H···Br [Br2···N1 of 3.386(13) ? and Br1···N1 of 3.363(13) ?] and C–H···Br [Br2···C5 of 3.552(16) ?] hydrogen bonding interactions, tying the CdBr chains to the cations to form 2D-network. The resulting 2D-networks are further linked by aryl···aryl (π···π) interactions within the cationic chains leading to a 3D-network. Index Abstract Three dimensional network polymeric structure of (4,4′-bipyridinium)[CdBr4] n : Supramolecular motifs and crystal supramolecularity. Rawhi Al-Far and Basem F. Ali The polymeric anion consists of a zig–zag chain of distorted edge shared octahedra run along c axis. The protonated cation bridges the anion chains through N–H···Br and C–H···Br into a supramolecular array.   相似文献   
7.
MoV ion complex in the [MoOBr5]2− anion is crystallized with 2,2′-bipyridinium dication. MoV is in a distorted octahedral environment at both 293 and 90 K, and is displaced from the plane of the four bromido ligands, with the Mo–Brtrans to the oxo ligand being significantly longer than the other equatorial bromido ligands. Extensive hydrogen bonding of the types (C,N)–H···(Br,O) and offset face-to-face interactions leading to a supramolecular crystal lattice that engineers the entrapment of [MoOBr5]2− anion. This is further stabilized by the Br···Br intermolecular interactions that hold the anionic network. The anisotropic cell contraction results in significant changes in nonbonding contacts. DFT calculations at the B3LYP level of theory using the pseudo potentials of “LANL2DZ” and “LANL2TZ (Mo)/6-31G*(C, N, Br, H)”, Slater Type Orbital (STO) and 3-21G basis sets were carried out. DFT calculations results from different basis sets were compared, and results show that the optimized calculated geometry is relatively consistent with the X-ray data and hence the observed structure for the complex is indeed possible. HOMO and LUMO orbitals and the energy gag were also determined.  相似文献   
8.
Abstract  A single crystal structure determination of the complexes (2,2′-bipyridinium)[MBr4], M = Zn, Hg and Co, have been carried out. It crystallizes in the monoclinic space group P21 /c. The structures consist of alternating stacks of anions and cations. They demonstrate a supramolecularity represented by the inter anion···cation, N–H···Br and C–H···Br interactions. The N–H···Br hydrogen bonding interactions, ca. 3.306(3)–3.213(7) ? and with angles spanning the range 154–156°, tying the MBr4 anions to the cations. Intra- and interstack anion···anion interactions represented by Br···Br interactions, also exist. All these interactions lead to a 3D-network. Index Abstract     相似文献   
9.
Abstract  Three salts of 2,5-dibromopyridinium with metal halides, (C5H4Br2N)2[CuCl4], (I); (C5H4Br2N)2[CuBr4], (II); and (C5H4Br2N)2[CdBr4], (III), are isomorphous in C2/c with cell volumes 1864.5(8), 1974.6(4) and 2072.9(7) ?3, respectively. For the Cu cases (I) and (II) the discrete [MX4]2− anions are strongly distorted with max/min tetrahedral angles of 131.19(8)°/99.67(9)° and 130.24(5)°/99.36(11)°, respectively. For the Cd case (III) the distortion is much less with max/min tetrahedral angles of 115.97(3)°/105.99(4)°. The cations are planar. The short hal···hal contacts are for (I), aryl Br···anionic Cl 3.335(3) ? and 3.430(2) ?; for (II), aryl Br···anionic Br 3.473(2) ? and 3.567(2) ?; and for (III), aryl Br···anionic Br 3.452(1) ? and 3.675(1) ?. Longer aryl Br···aryl Br contacts (3.842(2) ? to 3.967(2) ? are present in the three isomorphs. Bifurcated hydrogen bonding to two anionic halides exist in the three structures with N–H···Cl 3.365(8) ? and 3.379(7) ? in (I), N–H···Br 3.539(11) ? and 3.425(11) ? in (II), and N–H···Br 3.426(5) ? and 3.387(5) ? in (III). Short ring contacts exist with the perpendicular distances between mean cation planes in (I), (II), and (III) of 3.68(6) ?, 3.56(1) ? and 3.72(1) ?, respectively. Index Abstract  An analysis is made of the competition between hydrogen bonding, halogen–halogen and halogen–halide interactions as well as differences between [CuX4]2− and [CdX4] 2− polydedra in the structures of the three isomorphs.   相似文献   
10.
The salt bis(2-amino-5-methylpyridinium) hexabromostannate(IV) (C6H9N2)2[SnBr6] is monoclinic, P2 1 /c, with the following cell parameters: a=9.1636(18) ?, b=28.767(7) ?, c=16.956(17) ?, β=101.008(5)°, V=4387.5(17) ?3, Z=8, formula units. X-ray crystallography revealed that the structure can be regarded as a semi-regular three-dimensional array of anions, with pairs of cations forming layers perpendicular to b axis in the cavities between the anions. The cohesion forces that connects molecules in the organic layers are hydrophilic N⋯HCH2 and HN⋯HN hydrogen bonding as well as hydrophobic π-π stacking and CH3⋯π interactions. Cations and anions are connected via strong Br⋯H hydrogen bonding. Supplementary material CCDC 276493 contains the supplementary crystallographic data. These data can be obtained free of charge via www.ccdc. cam.ac.uk/data_request/cif, by e-mailing data_ request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(0)1223-336033.  相似文献   
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