Materials Literature
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Inner C-cyanide addition and subsequent addition of a methoxy group were observed in the reactions of Ni(II) N-confused tetra(p-tolyl)porphyrin with sodium methoxide and DDQ.
We apply the density-matrix renormalization-group (DMRG) technique to magnetic molecules in order to evaluate the low-lying energy spectrum. In particular, we investigate the giant Keplerate molecule ${{\mathrm{Mo}}_{72}{\mathrm{Fe}}_{30}}$ [A. M\"uller et al. Angew Chem. Int. Ed. Engl. $38,$ 3238 (1999)], where 30 ${…
Thin films of monodomain porous alumina with 2 µm thickness and adjustable monodisperse pore diameter are obtained via anodization of nanoimprinted Al evaporated on a Si wafer. By using these templates, hexagonally arranged monodisperse silver nanowires on Si are prepared by electrochemical deposition with a commercia…
Electronic structural change of single-walled carbon nanotubes induced by potassium encapsulation was studied by photoemission spectroscopy. The potassium encapsulation caused a shift of the overall valence-band spectrum toward the higher binding-energy side by about 0.5 eV, which is basically understood by the simple…
Using molecular-dynamics simulation with the embedded atom method, the dynamical properties of supercooled liquid Cu were studied by characterizing several time-correlation functions. With increasing undercooling of the liquid Cu below the melting point, self-diffusion slows down along with an increase in the structur…
A complete investigation of the complex magnetic behaviour of Gd 5 Ge 4 by means of linear thermal expansion and magnetostriction measurements (5–300 K, 0–120 kOe) has been carried out. Our results support the suggested existence in this system of a coupled crystallographic–magnetic transition from a Gd 5 Ge 4 -type P…
Single-crystal X-ray diffraction studies of brochantite demonstrate its Order-Disorder (OD) character. The OD structures of the brochantite family can be described as built up by equivalent OD layers with symmetry Pn2(1)m. Two MDO polytypes are possible in this family, and both have been identified in specimens of bro…
The temperature-dependent Nb K-edge absorption spectra of several mixed-ion Pb-containing perovskite compounds were analysed to determine the Nb displacement and to trace its changes through the phase transitions. Both extended x-ray absorption fine structure (EXAFS) and the pre-edge region of the spectra were involve…
Propanediols (1,2- and 1,3-propanediols) were reacted with methoxy-modified kaolinite to form hydroxypropoxy-modified kaolinites by transesterification. Grafting occurred on the AlOH groups of the interlayer surface, which provides unique asymmetrical interlayer environments surrounded by both hydroxy groups of the di…
We present an analytic calculation of the dielectric constant of graphite valid in the spectral range dominated by \ensuremath{\pi}-electron transitions. An orthogonal, nearest-neighbor tight-binding description of electron bands is applied and interaction between different graphite layers is ignored. In addition to t…
Abstract Nanocomposite materials of α-Fe/Y2O3 prepared by melt-spun technique exhibited good electromagnetic wave absorption properties (RL<−20 dB) in a 2.0-3.5 GHz range as absorbers with thickness ranging from 3 to 5 mm, and a minimum reflection loss of −36 dB was obtained at 2.6 GHz with an absorber thicknes…
Abstract The influence of ZnO nanoparticles on the crystalline structures of nylon‐6 under different crystallization conditions (annealing at different temperatures from the amorphous solid, isothermal crystallization from the melt at different temperatures, and crystallization from the solution) has been examined wit…
P-type transparent CuAlO 2 semiconductor films are made by the spin-on technique from nanocrystals. The nanocrystals are synthesized by a hydrothermal metathesis reaction. Scanning electron microscopy, x-ray diffraction and energy dispersive x-ray spectrometry suggest that the films contain nanocrystalline phases of C…
Systems of model planar, nonconvex, hard-body "molecules" of fivefold and sevenfold symmetry axes are studied by constant pressure Monte Carlo simulations with variable shape of the periodic box. The molecules, referred to as pentamers (heptamers), are composed of five (seven) identical hard disks "atoms" with centers…
We have studied the atomic structure of [001]90° rotation twin walls in orthorhombic CaTiO 3 (symmetry Pbnm ) at low temperature (10 K) and their effects on oxygen vacancies. The wall thickness was found to be 2.3 nm at T ≪ T c and it was found that it is energetically favourable for such vacancies to reside in the wa…
Pulsed laser deposited films of Co-doped anatase ${\mathrm{TiO}}_{2}$ are examined for Co substitutionality, ferromagnetism, transport, magnetotransport, and optical properties. Our results show limited solubility (up to \ensuremath{\sim}2%) of Co in the as-grown films and formation of Co clusters thereafter. For the…
Abstract The Raman spectrum of liquid ethyldibromosilane, CH 3 CH 2 SiHBr 2 , was recorded at various temperatures between 298 and 218 K, and the spectrum of the crystal was obtained at 210 K from a sample sealed in a capillary. Additional spectra of the amorphous and annealed crystals, which were deposited on a coppe…
Nanofibres of TiO 2 –SiO 2 (Ti:Si = 50: 50 mol%) with diameters of 50–400 nm were prepared by calcining electrospun nanofibres of polyvinyl acetate (PVac)/titania–silica composite as precursor. These PVac/titania–silica hybrid nanofibres were obtained from a homogenous solution of PVac with a sol–gel of titanium isopr…
By computer simulations of systems of ellipsoids, we study the influence of the isotropic/nematic phase transition on the direct correlation functions (DCF) in anisotropic fluids. The DCF is determined from the pair distribution function by solving the full Ornstein-Zernike equation, without any approximations. Using…
The Andreev reflection measurements of the superconducting energy gap in the carbon-substituted MgB$_2$ are presented. Despite the strong suppression of the transition temperature by 17 K in comparison with the pure MgB$_2$, the same reduced value of the small superconducting energy gap with $2Δ/kT_c \approx$ 1.7 has…