Materials Literature
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A weak ferromagnetic phase is shown in pressed pellets of partially doped poly(3-methylthiophene) (P3MT) in the whole range from 1.8 to 300 K in magnetic measurements. Thermoremanence data have been used to estimate the suppression of this phase to be around 815 K. We also show that instead of the classical antiferrom…
Abstract Polycrystalline CdS nanotubes (CNTs) were successfully achieved by a two‐step treatment, i.e. (CdS+Cd) nanowires (electrodeposition and sulfuration process in anodic alumina membrane) ⇄ CNTs (dissolution method of removing Cd in 0.5 M HCl). Having been characterized using X‐ray diffraction and scanning electr…
A detailed study of the electronic transport and magnetic properties of ${\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Cu}}_{x}{\mathrm{Cr}}_{2}{\mathrm{S}}_{4}$ $(x<~0.5)$ on single crystals is presented. The resistivity is investigated for $2<~T<~300\mathrm{K}$ in magnetic fields up to 140 kOe and under hydrosta…
We used the x-ray extended-range technique to measure the x-ray mass attenuation coefficients of silicon with an accuracy between 0.27% and 0.5% in the $5\mathrm{keV}\ensuremath{-}20\mathrm{keV}$ energy range. Subtraction of the x-ray scattering contribution enabled us to derive the corresponding x-ray photoelectric a…
The crystal and magnetic structures of the $A{\mathrm{LaMnMoO}}_{6}$ $(A=\mathrm{B}\mathrm{a},\mathrm{S}\mathrm{r})$ double perovskites have been studied. The Sr compound is monoclinic (space-group ${P2}_{1}/n)$ and does not exhibit long-range magnetic order. The crystal lattice of the Ba compound is pseudocubic, alth…
Abstract New polymethyloxazoline hydrogels are synthesized by the cationic ring‐opening copolymerization of 2‐methyl‐2‐oxazoline and 2,2′‐tetramethylenebis(2‐oxazoline), using random copolymers of chloromethylstyrene and methyl methacrylate, or of chloromethylstyrene and styrene as macroinitiators. The synthesis is ca…
The stability and electronic properties of various structures of carbon phosphide as well as other possible group IV-V compounds with 1:1 stoichiometry have been examined using first-principles calculations. Similar to CN, layered structures of CP are found to be energetically stable. Among all the structures consider…
The low-frequency single-particle and collective excitations of single-walled carbon nanotubes are studied in the presence of a magnetic field. They strongly depend on the magnitude and direction of the magnetic field, transferred momentum, temperature, nanotube geometry, and Zeeman splitting. A narrow-gap nonarmchair…
We use a family of embedded atom model potentials all based on accurate quantum-mechanical calculations to study the relation between Peierls stress and core properties of the $1/2a〈111〉$ screw dislocation in bcc tantalum (Ta). We find that the Peierls stress $({\ensuremath{\sigma}}_{P})$ is a function of the core-pol…
Using density functional theory results as input data into the tight binding method for induced representations (based on the line group symmetry concept) we calculate optical conductivity tensor for single wall carbon nanotubes. Optical transition matrix elements are calculated exactly, out of completely symmetry ada…
The crystal structures of a few phases of Ti such as hcp, bcc, $\ensuremath{\omega}$ (hexagonal phase) $\ensuremath{\gamma}$ (distorted hcp), $\ensuremath{\delta}$ (distorted bcc), and bcc under pressure have been studied by means of first-principles total-energy calculations in a generalized gradient approximation. O…
The line shape and intensity of surface and bulk plasmon excitations in Al $2s$ and $2p$ core-level spectra of Al(111) have been studied as functions of the photoelectron emission angle (\ensuremath{\theta}). For both surface and bulk plasmons, an asymmetric line shape is observed in normal emission, which becomes mor…
The paper presents a general formalism for the $n\mathrm{t}\mathrm{h}\ensuremath{-}\mathrm{n}\mathrm{e}\mathrm{a}\mathrm{r}\mathrm{e}\mathrm{s}\mathrm{t}\ensuremath{-}\mathrm{n}\mathrm{e}\mathrm{i}\mathrm{g}\mathrm{h}\mathrm{b}\mathrm{o}\mathrm{r}\phantom{\rule{0ex}{0ex}}\mathrm{d}\mathrm{i}\mathrm{s}\mathrm{t}\mathrm…
The optical properties of Ge and Si nanocrystals embedded in a crystalline matrix are calculated using an ab initio supercell method. Spectra of effective nanocrystallite materials including confinement effects are extracted by means of effective-medium theory. Spectra for different composites are calculated and compa…
Green ${\mathrm{Tb}}^{3+}{}^{5}{\stackrel{\ensuremath{\rightarrow}}{{\mathrm{D}}_{4}}}^{7}{\mathrm{F}}_{\mathrm{J}\mathrm{}}$ luminescence visible by eye is observed under near-infrared laser excitation. Optical spectroscopic techniques including absorption, luminescence, and excitation spectroscopy are used to charac…
The Gibbs-Bogolyubov inequality is used to establish a mapping between the Yukawa system and both the hard-sphere and the one-component reference systems. The transport coefficients of self-diffusion, shear viscosity, and thermal conductivity are computed for the Yukawa fluid using known properties of the reference sy…
The experimental magnetic susceptibility and heat capacity of ${\mathrm{LaCoO}}_{3}$ due to spin-state excitation in the range 2--300 K were well reproduced by a one-lattice molecular-field model with negative cooperative effect; an energy separation between the low-spin ground state and the excited state increases wh…
We have investigated the influence of post-deposition annealing on the optical and electrical properties of c -axis oriented zinc oxide films prepared on sapphire substrates by electron beam evaporation. The ZnO films as-deposited and annealed in air were colourless and transparent in visible range and had sharp ultra…
Abstract The Michael reaction of chitosan with acrylic acid was carried out successfully, even in water alone as the reaction medium. As a consequence of its good solubility in water, the reaction product, N ‐carboxyethylchitosan, showed excellent biodegradable properties with standard activated sludge. magnified image
The $2n+1$ theorem and the density-functional perturbation theory have been used to calculate anharmonic force constants completely ab initio. Explicit expressions for the anharmonic coupling constants are presented, i.e., for the third-order derivatives of the total energy with respect to atomic displacements. Using…