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Extended Dynamical Mean Field Theory and GW method

Ping Sun、Gabriel Kotliar2002-06-29arXiv

We develop the extended dynamical mean field theory (E-DMFT) with a view towards realistic applications. {\bf 1)} We introduce an intuitive derivation of the E-DMFT formalism. By identifying the Hartree contributions before the E-DMFT treatment, it allows to handle systems in symmetry breaking phases within a simple f…

Materials ScienceStrongly Correlated Electrons

Ferroelectric liquid crystalline polyoxetanes bearing chiral dimesogenic pendants

Jun-Woo Lee、Dong Keun Oh、C. V. Yelamaggad 等 5 位作者2002-06-28Journal of Materials Chemistry

Two new polyoxetanes bearing dimesogenic pendants were prepared and their liquid crystalline properties were studied by differential scanning calorimetry (DSC), polarizing microscopy, and X-ray diffractometry. The dimesogens consist of cholesterol and biphenyl moieties connected through polymethylene spacers. Their bi…

Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsPhotochromic and Fluorescence Chemistry

Improved Luminescence Properties and Thermal Stability of ZnS Quantum Dots by Organic and Inorganic Passivation

El-Khair Hatim Mohamed、Ling Xu、Kunji Chen 等 7 位作者2002-06-28Chinese Physics Letters

ZnS quantum dots (QDs) synthesized in water and ethanol solutions were coated with polystyrene (PS) and SiO 2 shells, respectively. The band edge emission was enhanced by nearly five times after PS coating and by about thirteen times after SiO 2 coating, because the surface trap states were removed. From the photolumi…

Quantum Dots Synthesis And PropertiesChalcogenide Semiconductor Thin FilmsNanocluster Synthesis and Applications

Atomic structure of the (Al,Si)CuFe cubic approximant phase

Fréderic Puyraimond、Marianne Quiquandon、D. Gratias 等 7 位作者2002-06-28Acta Crystallographica Section A Foundations of Crystallography

The structure of the alpha-(Al,Si)CuFe approximant phase is determined by a single-crystal X-ray diffraction study and compared to the ideal structure obtained by the perpendicular shear method of the parent icosahedral phase. It is shown that the local environments (typical atomic clusters) of the two phases are simi…

Microstructure and mechanical propertiesAluminum Alloy Microstructure PropertiesQuasicrystal Structures and Properties

Catalysis in electron transfer reactions: facts and mechanistic insights

Shunichi Fukuzumi2002-06-28Journal of Physical Organic Chemistry

Abstract Catalysis in electron transfer reactions between electron donors and acceptors is described and the important mechanistic insight is provided by showing a number of examples of both thermal and photochemical reactions that involve metal ion‐catalyzed electron transfer processes as the rate‐determining steps.…

Electrocatalysts for Energy ConversionPorphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer Studies

Phase behaviour of mixtures of polyethylene glycol and polypropylene glycol: Influence of hydrogen bond clusters on the phase diagram

Susanne Eckert、Gerhard Meier、I. Alig2002-06-28Physical Chemistry Chemical Physics

The phase behaviour of a binary polymer blend of polyethylene glycol (PEG600) and polypropylene glycol (PPG1000) of low polydispersity was investigated. The coexistence curves of five different compositions, including the critical composition, were measured by differential refractometry. From the coexistence curves, t…

Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesSurfactants and Colloidal Systems

Acid chloride‐functionalized hyperbranched polyester for facile and quantitative chain‐end modification: One‐pot synthesis and structure characterization

Nori Yamaguchi、Jin‐Shan Wang、J. Michael Hewitt 等 5 位作者2002-06-28Journal of Polymer Science Part A Polymer Chemistry

Abstract Carboxylic acid chloride end‐functionalized all‐aromatic hyperbranched polyesters were prepared from the bulk polycondensation of the AB 2 monomer 5‐(trimethylsiloxy)isophthaloyl dichloride. The acid chloride end functionality of the hyperbranched polyester was modified in situ with methanol and yielded methy…

RNA Interference and Gene DeliveryDendrimers and Hyperbranched PolymersSynthesis and properties of polymers

<title>Real-time seismic damping and frequency control of steel structures using nitinol wire</title>

Gary L. McGavin、Greg Guerin2002-06-28Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Thirty years ago, automotive engineers perfected real-time damping for vehicle suspension systems prior to hitting bumps in the road. In the near future, architects and structural engineers may be able to use the same philosophy for tuning structures to withstand earthquakes as their waves impinge on the structure. Co…

Structural Health Monitoring TechniquesShape Memory Alloy TransformationsStructural Engineering and Vibration Analysis

Synthesis and Properties of Photoluminescent 1,4-Bis-(α-cyano-4-methoxystyryl)benzenes

Christoph Weder、Christiane Löwe2002-06-28Synthesis

1,4-Bis-(α-cyano-4-methoxystyryl)benzene (1a) and 1,4-bis-(α-cyano-4-methoxystyryl)-2,5-dimethoxybenzene (1b) were synthesized by the Knoevenagel reaction of (4-methoxyphenyl)acetonitrile with terephthaldicarboxyaldehyde and 2,5-dimethoxy terephthaldicarboxyaldehyde, respectively. Both phenylene vinylene oligomers are…

Photochromic and Fluorescence ChemistrySynthesis and properties of polymersPhotopolymerization techniques and applications

Spectroscopic and Spectroelectrochemical Properties of a Poly(alkylthiophene)−Oligoaniline Hybrid Polymer

Bruno Dufour、Patrice Rannou、J.P. Travers 等 9 位作者2002-06-28Macromolecules

By copolymerization of 3-octylthiophene with thiophene containing aniline tetramer in the 3-position we have prepared a hybrid copolymer, poly(3-octyl-2,5-thienylene- co -3-oligoaniline-2,5-thienylene), exhibiting very interesting spectroscopic and spectroelectrochemical properties. The UV−vis−NIR spectrum of this new…

Organic Electronics and PhotovoltaicsPerovskite Materials and ApplicationsConducting polymers and applications

Structure of nanocrystalline anatase solved and refined from electron powder dataPresented at the microsymposium onElectron Crystallography of Small Molecules and Organic Materials, 19th European Crystallographic Meeting, Nancy, France, 25–31 August 2000.

Thomas E. Weirich、Markus Winterer、S. Seifried 等 4 位作者2002-06-28Acta Crystallographica Section A Foundations of Crystallography

Energy-filtered Debye-Scherrer electron powder data have been successfully employed to determine the structure of nanocrystalline anatase (TiO2). The performed structure analysis includes determining the unit cell, space group, solving the structure via direct methods from extracted intensities and refining the struct…

Crystal Structures and PropertiesMetal Extraction and BioleachingX-ray Diffraction in Crystallography

DNA Photocleavage by a Supramolecular Ru(II)−Viologen Complex

Patty K.‐L. Fu、Patricia M. Bradley、Dietmar van Loyen 等 6 位作者2002-06-28Inorganic Chemistry

A novel Ru(II) complex possessing two sequentially linked viologen units, Ru-V(1)-V(2)(6+), was synthesized and characterized. Upon excitation of the Ru(II) unit (lambda(exc) = 532 nm, fwhm approximately 10 ns), a long-lived charge-separated (CS) state is observed (tau = 1.7 micros) by transient absorption spectroscop…

Metal complexes synthesis and propertiesPorphyrin and Phthalocyanine ChemistryMetal-Catalyzed Oxygenation Mechanisms

Structure of the Photocolored 2-(2‘,4‘-Dinitrobenzyl)pyridine Crystal: Two-Photon Induced Solid-State Proton Transfer with Minor Structural Perturbation

Pancě Naumov、Akiko Sekine、Hidehiro Uekusa 等 4 位作者2002-06-28Journal of the American Chemical Society

The X-ray structure of the blue phototautomer of 2-(2',4'-dinitrobenzyl)pyridine (DNBP) produced by two-photon excitation in a single crystal is the first direct evidence of a product in the DNBP photochromic family. A nitro-assisted proton transfer mechanism is attributed to the photocoloration of solid DNBP.

Porphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer StudiesPhotochromic and Fluorescence Chemistry

Bubble size distribution estimation via void rate dissipation in gas saturated liquid. Application to ultrasonic cavitation bubble fields

Stéphane Labouret、Jacques Frohly2002-06-28The European Physical Journal Applied Physics

A hyper-frequency method enabling to investigate into the bubble size distribution of a bubble cloud in which bubble radii are lower than the equilibrium one is displayed. It is based on analysing the void rate dissipation after the acoustic irradiation is switched off in terms of bubble dissolution. The experimental…

Fluid Dynamics and MixingMinerals Flotation and Separation TechniquesUltrasound and Cavitation Phenomena

Thermolysis of gold(i) thiolate complexes producing novel gold nanoparticles passivated by alkyl groups

Masami Nakamoto、Masaki Yamamoto、Masao Fukusumi2002-06-28Chemical Communications

Thermolysis of gold(I) thiolate complex, [C14H29(CH3)3N][Au(SC12H25)2], at 180 degrees C for 5 h under an N2 atmosphere produces novel gold nanoparticles passivated by alkyl groups derived from the precursor complex, the TEM image of which shows spherical particles with average diameter 26 nm.

Gold and Silver Nanoparticles Synthesis and ApplicationsMolecular Junctions and NanostructuresNanocluster Synthesis and Applications

H-function representations for stretched exponential relaxation and non-Debye susceptibilities in glassy systems

R. Hilfer2002-06-28Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Analytical expressions in the time and frequency domains are derived for non-Debye relaxation processes. The complex frequency-dependent susceptibility function for the stretched exponential relaxation function is given for general values of the stretching exponent in terms of H-functions. The relaxation functions cor…

Material Dynamics and PropertiesGlass properties and applicationsThermodynamic properties of mixtures

The first coordination compound containing three different types of spin carriers: 2p–3d–4f (TCNQ˙–, Cu2+ and Gd3+)

Augustin M. Mădălan、Herbert W. Roesky、Marius Andruh 等 5 位作者2002-06-28Chemical Communications

A novel heterospin system, [(CuL)2Gd(TCNQ)2].TCNQ-.CH3OH.2CH3CN, is obtained by reacting the mononuclear complex, [CuL], with gadolinium(III) nitrate, followed by the substitution of the nitrato ions with anionic organic radicals.

Magnetism in coordination complexesLanthanide and Transition Metal ComplexesOrganic and Molecular Conductors Research

Surface half-metallicity of CrAs in the zinc-blende structure

I. Galanakis2002-06-28Physical review. B, Condensed matter

The development of new techniques such as the molecular beam epitaxy have enabled the growth of thin films of materials presenting novel properties. Recently it was made possible to grow a CrAs thin-film in the zinc blende structure. In this contribution, the full-potential screened KKR method is used to study the ele…

Magnetic properties of thin filmsQuantum and electron transport phenomenaHeusler alloys: electronic and magnetic properties

Femtosecond snapshots of gap-forming charge-density-wave correlations in quasi-two-dimensional dichalcogenides1T−TaS2and2H−TaSe2

J. Demšar、Lászlø Forró、H. Berger 等 4 位作者2002-06-28Physical review. B, Condensed matter

Time-resolved optical spectroscopy of collective and single-particle excitations of $1T\ensuremath{-}{\mathrm{TaS}}_{2}$ and $2H\ensuremath{-}{\mathrm{TaSe}}_{2}$ reveals the presence of a large gap in the excitation spectrum on the femtosecond time scale, associated with the formation of various degrees of charge-den…

Perovskite Materials and Applications2D Materials and ApplicationsOrganic and Molecular Conductors Research

Decoupling Optical and Potentiometric Band Gaps in π-Conjugated Materials

Kimihiro Susumu、Michael J. Therien2002-06-28Journal of the American Chemical Society

Syntheses, optical spectroscopy, potentiometric studies, and electronic structural calculations are reported for two classes of conjugated (porphinato)metal oligomers that feature a meso-to-meso ethyne-bridged linkage topology. One set of these systems, bis[(5,5'-10,20-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphi…

Molecular Sensors and Ion DetectionPorphyrin and Phthalocyanine ChemistryLuminescence and Fluorescent Materials