Concept

Polarité (chimie)

Publications associées (273)

Formation of Microcapsules from Polyelectrolyte and Covalent Interactions

Urs von Stockar, Ian William Marison, Véronique Breguet, Raphaël Gugerli, Mimma Pernetti

A new approach combining electrostatic and covalent bonds was established for the formation of resistant capsules with long-term stability under physiol. conditions. Three kinds of interactions were generated in the same membrane: (1) electrostatic bonds b ...

2005

Searching for molecular arene hydrogenation catalysis in ionic liquids

Paul Joseph Dyson

Arene hydrogenation by homogeneous catalysts is a highly controversial area of research, with many of the mononuclear complexes shown to catalyse the reaction, being found to be pre-catalysts to nanoparticles, on closer examination. The solvent properties ...

2005

Ab initio molecular dynamics of liquid hydrogen chloride

Alfredo Pasquarello

We carried out an ab initio molecular dynamics simulation of liquid hydrogen. chloride (l-HCl) at a temperature of 313 K. Comparison with inelastic neutron scattering data shows that the simulation achieves an overall good description of the structural cor ...

2005

Dipole moments of HDO in highly excited vibrational states measured by Stark induced photofragment quantum beat spectroscopy

Thomas Rizzo, Patrice Theulé

We report here a measurement of electric dipole moments in highly vibrationally excited HDO molecules. We use photofragment yield detected quantum beat spectroscopy to determine electric field induced splittings of the J=1 rotational levels of HDO excited ...

2005

Performance of optimized atom-centered potentials for weakly bonded systems using density functional theory

Ursula Röthlisberger, Ivano Tavernelli, Anatole von Lilienfeld

Recently, we have introduced a scheme for optimizing atom-based nonlocal external potentials within the framework of d. functional theory (DFT) in order to systematically improve the description of mol. properties [Phys. Rev. Lett. 93, 153004 (2004); J. Ch ...

2005

Structure of nitrile-functionalized alkyltrifluoroborate salts

Paul Joseph Dyson, Zhaofu Fei, Dongbin Zhao

Two nitrile-functionalized alkyltriflouroborate anion based complexes [(Ph3P)(2)N][CH3CH(BF3)CH2CN] and [K(18-crown-6)][CH3CH(BF3)CH2CN] were synthesized and characterized by spectroscopic methods and single X-ray diffraction analysis. In the former comple ...

2005

One or more C-H bond(s) formed by substitution: reduction of carbon-nitrogen, -phosphorus, -arsenic, -antimony, -bismuth, -carbon, -boron and -metal bonds

Jieping Zhu, Juliette Ferial Blanchet

The following chapter summarizes the various methodologies allowing the reductive cleavage of various carbon---hetereroatom single bonds or multiple bonds naming the transformation of C---N bond, C---P, C---As, C---Sb, C---Bi, C---C, C---Si, C---Ge, C---B, ...

Elsevier Pergamon2005

Beam-induced etching of material on substrate involves directing gaseous compound which reacts in the presence of beam to etch the excess material which not etching the substrate

Patrik Willi Hoffmann, Tristan Bret, Xavier Multone

A method and apparatus for local beam processing using a beam activated gas to etch material are described. Compounds are disclosed that are suitable for beam-induced etching. The invention is particularly suitable for electron beam induced etching of chro ...

FEI CO (FEIF-Non-standard)2005

Correlation between dielectric anisotropy and positive or zero transverse piezoelectric coefficients in perovskite ferroelectric single crystals

Nava Setter, Dragan Damjanovic, Matthew Davis

The transverse piezoelectric coefficient (d(31)(star)) has been calculated for tetragonal barium titanate (BT) and lead titanate (PT) cut along nonpolar axes, over a range of temperatures, using the phenomenological Landau-Ginzburg-Devonshire theory. It is ...

2005

Ab initio transport properties of nanostructures from maximally localized Wannier functions

Nicola Marzari

We present a comprehensive first-principles study of the ballistic transport properties of low-dimensional nanostructures such as linear chains of atoms (Al, C) and carbon nanotubes in the presence of defects. An approach is introduced where quantum conduc ...

2004

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