Search results for "Stacking"
showing 10 items of 215 documents
Different regimes of electronic coupling and their influence on exciton recombination in vertically stacked InAs/InP quantum wires
2006
8 páginas, 8 figuras.
The polar method as a tool for solving inverse problems of the classical laminated plate theory
2000
Publisher Summary Fiber reinforced laminates are widely used in modem applications. For these kinds of structures, the Classical Laminated Plate Theory and its various extensions provide efficient methods for theoretical analysis, that is, when the stacking sequence, the orientations, and the properties of the individual laminas are known. For design of laminates, a very limited number of rules are available. For stiffriess design, two are currently known and used in practical applications: the Werren and Norris rule to get membrane isotropy, and the symmetrical sequence rule to suppress stretching/bending coupling. This chapter deals with the resolution of inverse problems of the Classical…
3-(4-Fluorophenyl)-1-methyl-4-(4-pyridyl)quinolin-2(1H)-one
2007
The title compound, C21H15FN2O, was synthesized in the course of our studies of p38 mitogen-activated protein kinase inhibitors. It has been investigated by 1H and 13C NMR spectroscopy and was proven by X-ray crystallographic analysis to be the N-methyl rather than the O-methyl isomer. In the crystal structure, a three-dimensional network is formed consisting of quinolinone aromatic stacking interactions and weak C—H⋯O and C—H⋯N hydrogen bonds.
1-(2,3,5,6-Tetramethylbenzyloxy)-1H-benzotriazole
2009
In the title compound, C17H19N3O, the benzotriazole ring is essentially planar, with a maximum deviation of 0.0069 (15) Å. The mean plane of the benzotriazole ring forms a dihedral angle of 13.16 (4)° with the mean plane of the benzene ring. The crystal packing is stabilized by π–π stacking interactions, with a centroid–centroid distance of 3.8077 (12) Å, together with weak C—H...π interactions. Molecules are stacked along the a axis.
Self-assembled hydrogen-bonded coordination networks in two copper(II) carboxylates with 4-pyridylmethanol
2011
AbstractThe crystal and molecular structure of [Cu(nif)2(4-PM)2]·CH3OH (1) and [Cu(2-Clbz)2(4-PM)2(H2O)] (2), (where nif = niflumate anion, 2-Clbz = 2-chlorobenzoate anion and 4-PM is the 4-pyridylmethanol), have been determinated by X-ray crystallography. The Cu2+ cation in (1), is coordinated by two pairs of oxygen atoms from asymmetric bidentate niflumate anions and by a pair of pyridine nitrogen atoms from monodentate 4-pyridylmethanol ligands in trans position forming an extremely elongated bipyramid. The Cu2+ cation in (2), is coordinated by a pair of oxygen atoms from monodentate 2-chlorobenzoate anions, further by a pair of pyridine nitrogen atoms from monodentate 4-pyridylmethanol …
Supramolecular order of stilbenoid dendrons: importance of weak interactions
2006
Stilbenoid dendrons with various donor and acceptor groups on the focal unit were synthesised by a Wittig–Horner reaction, starting from an aldehyde functionalised dendron and various substituted phosphonic acid esters. The target molecules are composed of meta-branched arms, two of them with extended conjugation (distyrylbenzene) and three flexible dodecyloxy chains; the focal group consists of a donor or acceptor substituted styryl unit. The cross-conjugation of the arms prevents the strong electronic influence of substituents on the two extended oligophenylenevinylene chromophores. However, intermolecular interactions mediated by the focal unit allow control of the supramolecular stackin…
ChemInform Abstract: Areno-Condensed Annulenes - Extended Discotic Mesogens.
2010
[n]Annulenes (n ≥12) condensed with 2-4 aromatic ring systems (benzenes, naphthalenes, anthracenes, phenanthrenes, chrysenes, pyrenes) can be prepared by cyclocondensation reactions or ring transformations. Due to the local arene aromaticity, the molecules can be regarded as aromatic islands, which are connected by olefinic bridges. The compounds are non-planar, but the majority of the systems shows a fast inversion of the central macrocyclic ring, so that the molecules appear on average as large planar discs, which consist of extended π systems. The aggregation tendency (π stacking) of the compounds can be strengthened by the attachment of flexible saturated chains on the periphery. The di…
2,2-Dimethyl-N-[3-(3,4,5-trimethoxybenzoyl)pyridin-4-yl]propanamide
2007
The title compound, C20H24N2O5, was found to have an intramolecular N—H⋯O bond with an N⋯O distance of 2.646 (2) A. In the crystal structure, molecules form dimers along the c axis by aromatic stacking interactions. The X-ray crystallographic analysis was carried out to correlate the solid-state geometry with virtual structural information obtained by modelling.
2-(Benzylsulfanyl)pyridineN-oxide
2008
In the title compound, C12H11NOS, the dihedral angle between the oxopyridinium and phenyl rings is 58.40 (1)°. The crystal structure is stabilized by C—H...O hydrogen bonds, π–π stacking interactions involving the pyridinium rings [centroid–centroid distance = 3.6891 (9) Å] and C—H...π interactions.
Detailed study of defects in thin fullerite films
2012
The structural investigations of fullerite films were performed using high-resolution electron microscopy, electron diffraction and electron energy loss spectroscopy and X-ray photoelectron spectroscopy. In particular defects such as dislocations, stacking faults and twins were studied in details. It was shown that fullerite films could be characterized by a face-centered cubic (f.c.c.) structure with lattice parameter a = 1.416 nm. They are distinguished for their rich polytypic structure that is caused by breaking of alteration of closely packed planes of (111) type. The quantitative method based on information theory using the “run-length encoding” algorithm was suggested to evaluate the…