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Chains Parallel (chain + parallel)
Selected Abstracts(E)- N -{[6-Chloro-4-(4-chlorophenyl)-3-methyl-1-phenyl-1H -pyrazolo[3,4- b]pyridin-5-yl]methylene}benzene-1,2-diamine: a three-dimensional framework structure built from only two hydrogen bondsACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2010Yurina Díaz The molecules of the title compound, C26H19Cl2N5, are conformationally chiral, with none of the aryl groups coplanar with the pyrazolo[3,4- b]pyridine core of the molecule. A single unique N,H...N hydrogen bond links the molecules into two symmetry-related sets of C(11) chains running parallel to the [011] and [01] directions, respectively, and these two sets of chains are linked into a continuous three-dimensional framework structure by a single unique C,H...N hydrogen bond which forms a chain parallel to the [100] direction. [source] Polymorph of {2-[(2-hydroxyethyl)iminiomethyl]phenolato-,O}dioxido{2-[(2-oxidoethyl)iminomethyl]phenolato-,3O,N,O,}molybdenum(VI)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2008Dominique Agustin A second polymorphic form (form I) of the previously reported compound {2-[(2-hydroxyethyl)iminiomethyl]phenolato-,O}dioxido{2-[(2-oxidoethyl)iminomethyl]phenolato-,3O,N,O,}molybdenum(VI) (form II), [Mo(C9H9NO2)O2(C9H11NO2)], is presented. The title structure differs from the previously reported polymorph [G,owiak, Jerzykiewicz, Sobczak & Zió,kowski (2003). Inorg. Chim. Acta, 356, 387,392] by the fact that the asymmetric unit contains three molecules linked by O,H...O hydrogen bonds. These trimeric units are further linked through O,H...O hydrogen bonds to form a chain parallel to the [11] direction. As in the previous polymorph, each molecule is built up from an MoO22+ cation surrounded by an O,N,O,-tridentate ligand (O,C6H4CH=NCH2CH2O,) and weakly coordinated by a second zwitterionic ligand (O,C6H4CH=N+HC2H4OH). All complexes are chiral with the absolute configuration at Mo being C or A. The main difference between the two polymorphs results from the alternation of the chirality at Mo within the chain. [source] Synthesis and X-ray structure of two conformational isomers of [Zn(medpt)(SCN)2], medpt = bis (3 , aminopropyl)methylamineCRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2006S. Guha Abstract Two conformational isomers of [Zn (medpt)(NCS)2], medpt=bis(3-aminopropyl) methylamine, (1) and (2) have been synthesised and the crystal structures are determined using single crystal X-ray diffraction. The structures of the complexes have been solved by Patterson method and refined by full-matrix least- squares techniques to R1 = 0.0524 for (1) and R1 = 0.0506 for (2), respectively. The geometry around the Zn(II) centre in both isomers is distorted trigonal bipyramidal. The two pendent thiocyanate moieties in (1), with Zn,N,C angles 167.9(4),173.9(4)º, coordinate the mental centre almost linearly while the corresponding coordinations in (2) are significantly bent [Zn,N,C angles 150.8(3),153.1(2)°]. Intermolecular N,H,S hydrogen bonds stabilise the crystal packing in the complexes forming infinite chains parallel to the [100] direction. The combinations of molecular chains generate three/two dimensional supramolecular framework in complexes (1) and (2). (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Structural study of monoclinic KGd(WO4)2 and effects of lanthanide substitutionJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 1 2001M. C. Pujol The crystal structure of monoclinic KGd(WO4)2 (KGW) has been refined at room temperature by using single-crystal X-ray diffraction data. The unit-cell parameters are a = 10.652,(4), b = 10.374,(6), c = 7.582,(2),Å, , = 130.80,(2)°, with Z = 4, in space group C2/c. The linear thermal expansion tensor has been determined and the principal axes are [302], [010] and [106]. The principal axis with maximum thermal expansion ( = 23.44 × 10,6,K,1), , was located 12° from the c axis. Undoped crystals of KGW and crystals that were partially doped by Pr, Nd, Ho, Er, Tm and Yb were grown by the top-seeding-solution growth slow-cooling method. The effect of doping on the KGW structure was observed in the cell parameters and in morphological changes. The changes in parameters follow the changes in lanthanide ionic radii. The doped crystals show {021} and {21} faces in addition to the {110}, {11}, {010}, {130} and {310} faces which basically follow the habit of the undoped KGW crystals. The development of the faces is related to the number of the most important periodic bond chains parallel to them. [source] 4-Methoxyanilinium tetrafluoroborate,dibenzo-18-crown-6 (1/1)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010Xue-qun Fu In the structure of the complex of dibenzo-18-crown-6 [systematic name: 2,5,8,15,18,21-hexaoxatricyclo[20.4.0.09,14]hexacosa-1(26),9,11,13,22,24-hexaene] with 4-methoxyanilinium tetrafluoroborate, C7H10NO+·BF4,·C20H24O6, the protonated 4-methoxyanilinium (MB-NH3+) cation forms a 1:1 supramolecular rotator,stator complex with the dibenzo-18-crown-6 molecule via N,H...O hydrogen bonds. The MB-NH3+ group is attached from the convex side of the bowl-shaped crown, in contrast with similar ammonium cations that nest in the curvature of the bowl. The cations are associated via C,H..., interactions, while the cations and anions are linked by weak C,H...F hydrogen bonds, forming cation,crown,anion chains parallel to [011]. [source] Three quinolone compounds featuring O...I halogen bondingACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009Jurica Bauer Ethyl 1-ethyl-6-iodo-4-oxo-1,4-dihydroquinoline-3-carboxylate, C14H14INO3, (I), and ethyl 1-cyclopropyl-6-iodo-4-oxo-1,4-dihydroquinoline-3-carboxylate, C15H14INO3, (II), have isomorphous crystal structures, while ethyl 1-dimethylamino-6-iodo-4-oxo-1,4-dihydroquinoline-3-carboxylate, C14H15IN2O3, (III), possesses a different solid-state supramolecular architecture. In all three structures, O...I halogen-bonding interactions connect the quinolone molecules into infinite chains parallel to the unique crystallographic b axis. In (I) and (II), these molecular chains are arranged in (101) layers, via,,, stacking and C,H..., interactions, and these layers are then interlinked by C,H...O interactions. The structural fragments involved in the C,H...O interactions differ between (I) and (II), accounting for the observed difference in planarity of the quinolone moieties in the two isomorphous structures. In (III), C,H...O and C,H..., interactions form (100),molecular layers, which are crosslinked by O...I and C,H...I interactions. [source] A new polymorph of poly[bis(,2 -perchlorato-,2O:O,)(2,2,:6,,2,,-terpyridine-,3N,N,,N,,)lead(II)] with a greatly extended chain repeat distanceACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2009Alexander J. Blake In the title compound, [Pb(ClO4)2(C15H11N3)]n, two molecules occupy general positions while the third lies on a crystallographic twofold axis, giving a total of two and a half molecules per asymmetric unit. Each metal centre is coordinated equatorially by three 2,2,:6,,2,,-terpyridine (terpy) N-donor atoms and axially by two perchlorate O-donor atoms. The distorted pentagonal bipyramidal geometry is completed by two equatorial O-donor atoms from two perchlorate anions which bridge to two different adjacent metal centres. The coordination about each metal centre is very similar to that seen at the unique PbII centre in the previously published polymorph [Engelhardt, Harrowfield, Miyamae, Patrick, Skelton, Soudi & White (1996). Aust. J. Chem.49, 1135,1146], but the new polymorph differs from it by the insertion on each side of an existing [bis(perchlorato)(terpy)lead(II)] molecule of two additional such units. Pairs of asymmetrically bridging perchlorate anions link irregularly spaced PbII centres into undulating chains parallel to [201] which exhibit a repeat distance of 26.280,(4),Å. The significance of this new polymorph lies in the fact that, while it is chemically identical to the known polymorph, it is structurally distinct from it. [source] Di- tert -butyl ketone hydrazone and di- tert -butyl ketone triphenylphosphoranylidenehydrazoneACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2006Claude Villiers Reaction of di- tert -butyl ketone with hydrazine hydrate gives di- tert -butyl ketone hydrazone, C9H20N2, which is dimerized by double hydrogen bonding in the solid state. Further reaction of this compound with dibromotriphenylphosphorane gives di- tert -butyl ketone triphenylphosphoranylidenehydrazone, C27H33N2P, in the structure of which double chains parallel to the c axis are formed through weak C,H,, and ,,, stacking interactions. The hydrazone group is nearly planar in both cases. In the second compound, one of the aromatic rings is nearly coplanar with the hydrazone moiety, indicating possible ,-conjugation. [source] | ||||||||||