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Parallel Chains (parallel + chain)
Selected AbstractsManganese(II) and cobalt(II) complexes of 1,4-bis(diphenylphosphinoyl)butaneACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2009Anthony M. J. Lees The title complexes, catena -poly[[[diaquadiethanolmanganese(II)]-,-1,4-bis(diphenylphosphinoyl)butane-,2O:O,] dinitrate 1,4-bis(diphenylphosphinoyl)butane solvate], {[Mn(C2H6O)2(C28H28O2P2)(H2O)2](NO3)2·C28H28O2P2}n, (I), and catena -poly[[[diaquadiethanolcobalt(II)]-,-1,4-bis(diphenylphosphinoyl)butane-,2O:O,] dinitrate 1,4-bis(diphenylphosphinoyl)butane solvate], {[Co(C2H6O)2(C28H28O2P2)(H2O)2](NO3)2·C28H28O2P2}n, (II), are isostructural and centrosymmetric, with the MII ions at centres of inversion. The coordination geometry is octahedral, with each metal ion coordinated by two trans ethanol molecules, two trans water molecules and two bridging 1,4-bis(diphenylphosphinoyl)butane ligands which link the coordination centres to form one-dimensional polymeric chains. Parallel chains are linked by hydrogen bonds to uncoordinated 1,4-bis(diphenylphosphinoyl)butane molecules, which are bisected by a centre of inversion. Further hydrogen bonds, weak C,H...O interactions to nitrate anions, and weak C,H..., interactions serve to stabilize the structure. This study reports a development of the coordination chemistry of bis(diphenylphosphinoyl)alkanes, with the first reported structures of complexes of the first-row transition metals with 1,4-bis(diphenylphosphinoyl)butane. [source] Pressure effects on the structural, electronic, and optical properties of Sin@SWCNTsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 6 2009Y. H. Zhang Abstract Well-ordered single, double/four parallel, three/four-strands helical chains, and five-strand helical chain with a single atom chain at the center of Si nanowires (NWs) inside single-walled carbon nanotubes (Sin@SWCNTs) are obtained by means of molecular dynamics. On the basis of these optimized structures, the structural evolution of Sin@SWCNTs subjected to axial stress at low temperature is also investigated. Interestingly, the double parallel chains depart at the center and transform into two perpendicular parts, the helical shell transformed into chain, and the strand number of Si NWs increases during the stress load. Through analyzis of pair correlation function (PCF), the density of states (DOS), and the z -axis polarized absorption spectra of Sin@SWCNTs, we find that the behavior of Sin@SWCNTs under stress strongly depends on SWCNTs' symmetry, diameter, as well as the shape of NWs, which provide valuable information for potential application in high pressure cases such as seabed cable. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [source] catena -Poly[bis(trimethylphenylammonium) [hexa-,-chlorido-dichloridotricuprate(II)]]: an alternating zigzag chain of CuCl4 and Cu2Cl6 complexesACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010Marcus R. Bond The title compound, {(C9H14N)2[Cu3Cl8]}n, consists of parallel chains of alternating quasiplanar Cu2Cl6 and planar CuCl4 complexes separated by trimethylphenylammonium cations. Both inorganic complexes possess inversion symmetry. Pairs of neighboring chloride ions of the CuCl4 complex each form a symmetric bridge and an asymmetric bridge to Cu2Cl6 complexes on either side. The Cu2Cl6 complex contains two symmetric chloride bridges between the copper cations with a terminal chloride bound to each five-coordinated CuII ion. The CuCl4 complex completes its coordination environment by forming two long semicoordinate contacts to the bridging chloride ions of neighboring Cu2Cl6 complexes. The use of the bridging rather than the terminal chloride ions to form semicoordinate contacts generates a new zigzag chain structure that differs from the straight chain structures found for other A2Cu3Cl8 compounds. The zigzag chain structure is adopted so as to conform to the shorter repeat distance dictated by stacking of the organic cations. [source] A cyanide-bridged FeII,NdIII bimetallic assembly with a one-dimensional ladder-like chain structureACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2009Yan Xu The title complex, catena -poly[[[(2,2,-bipyridine-1,2N,N,)tris(methanol-2,O)(nitrato-2,2O,O,)-,-cyanido-1:2C:N -cyanido-1,C -iron(II)neodymium(III)]-di-,-cyanido-1:2,C:N;2:1,N:C] methanol solvate], {[FeIINdIII(CN)4(NO3)(C10H8N2)(CH3OH)3]·CH3OH}n, is made up of ladder-like one-dimensional chains oriented along the c axis. Each ladder consists of two strands based on alternating FeII and NdIII centers connected by cyanide bridges. Furthermore, two such parallel chains are connected by additional cyanide cross-pieces (the `rungs' of the ladder), which likewise connect FeII and NdIII centers, such that each [Fe(CN)4(bipy)]2, unit (bipy is 2,2,-bipyridine) coordinates with three NdIII centers and each NdIII center connects with three different [Fe(CN)4(bipy)]2, units. In the complex, the iron(II) cation is six-coordinated with a distorted octahedral geometry and the neodymium(III) cation is eight-coordinated with a distorted dodecahedral environment. [source] | ||||||||||