Materials Literature
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New ladder-type chromophores, the quaterrylenebis(dicarboxdiimide)s 2, 18 and 23, have been synthesised which, despite their extended π-system, exhibit good solubility in organic solvents and film forming properties when adequately substituted. These unprecedented dyes, which absorb and even emit light in the NIR wind…
In this paper it is demonstrated that colloidal assemblies used as templates are good candidates for controlling the size and shape of nanoparticles. The optical properties of metal nanoparticles dispersed in a colloidal solution differ with size and shape. When these particles are able to self-assemble, they form mon…
Abstract A first-order phase transition of CsSnCl3 to a cubic perovskite phase was observed at Ttr = 379 K. The electric conductivity increased from 10−6 S cm−1 to 10−3 S cm−1 at the phase transition. The temperature dependence of the electric conductivity and the X-ray diffraction data for CsSnCl3 suggested a reconst…
Upconversion fluorescence emission of Er3+/Yb3+-doped Bi2O3–Na2O–Nb2O5–GeO2 heavy metal glass samples excited at 1.06 μm is experimentally investigated. The results reveal the existence of intense emission bands centered around 520, 545, and 655 nm. The germano-niobate based host glass presents high transparency in th…
A combination of neutron powder diffraction and computer simulation techniques was performed on undoped and doped Bi2WO6 Aurivillius type compounds to clarify some of the factors controlling oxygen transport in these materials. Oxygen vacancies in doped compounds are randomly distributed within the perovskite-like sla…
A detailed review of inorganic lyotropic liquid crystals (water or water–organic dispersions of certain non-organic substances) is presented. The history of the discovery of these mesophases is described and their classification is considered. The structure and properties of all liquid crystals of this class known to…
We present a simple computational method to connect the computed ab initio values of static dipole polarizabilities and hyperpolarizabilities of molecules in solution with their experimental counterparts. The connection is done in terms of local field factors. We show that formulas used by experimentalists are not ade…
Laser-induced chemical vapor deposition of silicon carbonitride thin films has been investigated using a continuous wave CO2 laser in parallel configuration with the substrate. The reactant gases in this process, hexamethyl disilazane and ammonia, are rapidly heated by CO2 laser radiation due to their absorption of th…
The investigation of nanocrystalline materials has been an extremely active field during the past two decades as it promises to yield new and exciting properties, which will both test the scientific understanding of the behaviour of materials in general, and offer new scope for applications. While considerable progres…
A series of layered magnesium phyllo(organo)silicate nanocomposites that contain covalently linked organic functionalities have been prepared by a one-step, direct synthesis procedure. Organoclays with allyl, epoxy, imidazole or ethylenediamino functionalities were synthesized and characterized by XRD, TEM, FTIR and s…
The low-temperature growth and relaxation of misfitting films are analyzed on the basis of two-dimensional molecular dynamics simulations using Lennard–Jones potentials. The temporal evolution of the surface morphology and the mechanisms for misfit dislocation nucleation and stress relaxation are monitored. Pseudomorp…
Here we report for the first time, the extremely high and selective uptake of transition metal cations such as Cu2+, Ni2+, Co2+ and Zn2+ by two anionic clays of nominal composition, [Mg6Al2(OH)16 ]2+[CO3·4H2O]2– and [Mg2Al(OH)6 ]+[NO3·2H2O]–. We postulate that the principal mechanism of this selective cation uptake is…
The characterization of the heterocyclic radical 1,2,5-thiadiazolo[3,4- b ]-1,3,2-dithiazolo[3,4- b ]pyrazin-2-yl (TDP-DTA) is described. The compound is prepared by treatment of 5,6-dithiolo-1,2,5-thiadiazolo[3,4- b ]pyrazine with S 3 N 3 Cl 3 and purified by fractional sublimation in vacuo. The results of cyclic vol…
The photomerocyanines resulting from the UV irradiation of closed colourless 3,3-diphenyl-3H-naphtho[2,1-b]pyran and its 3,3-bis(4-fluorophenyl) derivative have been studied by UV–VIS and NMR spectroscopy.Kinetic bleaching studies have been carried out on a UV–VIS spectrometer at the photostationary state in acetonitr…
In general, materials have different magnetic susceptibilities depending on the crystal orientation and the magnetic field inside a material is different from the imposed magnetic field due to demagnetization depending on the susceptibility and the shape of materials. The utilization of this property will enable us no…
As a means of preparation of biocompatible molecular surfaces, an alternate assembly of charged polysaccharides and oppositely-charged synthetic polymers was conducted. Cationic chitosan was assembled alternately with anionic poly(sodium styrenesulfonate) (PSS) at pH 4. Regular film growth and its dependence on ionic…
Copper–organodiamine substructures are effective bridging groups for polyoxomolybdate anions in the construction of two-dimensional mixed metal networks, of which [{Cu(bpe)}4(α-Mo8O26)]·2H2O and [{Cu(pyrd)}4(γ-H4Mo8O26)] are representative [bpe = 1,2-bis(4-pyridyl)ethylene; pyrd = pyridazine].
Strong isotropic negative thermal expansion (α = –4.2 × 10–6 K–1) found for siliceous faujasite over a temperature range of 25 to 573 K is attributed to transverse vibrations of the bridging oxygen atoms, a model supported by structural refinements of X-ray diffraction data as a function of temperature.
Reactions between [M(H2O)3(tacn)]3+ (M = Cr, Co) and [Co(CN)3(tacn)] are demonstrated to produce the molecular box clusters [Cr4Co4(CN)12(tacn)8]12+ and [Co8(CN)12- (tacn)8]12+ with core structures consisting of a single cubic unit excised from the Prussian Blue type framework.
It is shown that the solid‐state equilibrium configuration of Bi‐doped ZnO grain boundaries is a nanometer‐thick amorphous film. Polycrystalline Bi‐doped ZnO was investigated using high‐resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM). The equilibrium state below…