Materials Literature
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Zn O ∕ Zn 0.8 Mg 0.2 O multiple-quantum-well (MQW) nanorods with a different number of periods and well widths were grown by catalyst-free metal-organic vapor phase epitaxy. Their optical and structural characteristics were investigated using photoluminescence, transmission electron microscopy, and field emission scan…
Oxygen vacancies in ${\mathrm{TbMnO}}_{3}$ were created by monovalent ${\mathrm{Na}}^{+}$ doping. The effects of the interruption of the superexchange paths on the spin orderings were investigated. Chemical doping resulted in a much higher ordering temperature, which is probably associated with enhanced $\mathrm{Tb}\t…
Combining first-principles calculations with a technique for many-body problems, we investigate properties of the transition metal oxide ${\rm Sr_{2}VO_{4}}$ from the microscopic point of view. By using the local density approximation (LDA), the high-energy band structure is obtained, while screened Coulomb interactio…
Chapter 10.2 discusses the relations between symmetry and the physical properties of crystals. The following properties and their dependence on the crystallographic point-group symmetries are described and presented in several tables: crystal morphology, symmetry of etch figures, optical birefringence, optical activit…
The authors report the self-assembly of hexagonal MnAs nanoclusters on GaInAs (111)B surfaces by metal-organic vapor phase epitaxy. The ferromagnetic behavior of the nanoclusters dominates the magnetic response of the samples when magnetic fields are applied in a direction parallel to the wafer plane. For the magnetic…
The authors demonstrate from their Raman and transmission electron microscopy results that the annealing ambient, temperature, and duration play a significant role in the formation, the evolution, and the crystallinity of Ge nanocrystals in silicon oxide matrix. With careful etching experiments, the authors establishe…
The authors report a cutting technique for carbon nanotubes (CNTs) assisted by the presence of oxygen gas. The cutting procedure is conducted in less than 1min using a low-energy electron beam inside a scanning electron microscope. The oxygen gas was regulated by a mass flow controller and was injected at 1SCCM. It wa…
We report molecular dynamics simulations for telechelic molecules composed of two polyhedral oligomeric silsesquioxane (POSS) cages connected by one hydrocarbon backbone dissolved in liquid normal hexane. Silsesquioxanes are novel hybrid organic-inorganic molecules that are useful as building blocks for the synthesis…
Abstract Calcium Carbonate has been precipitated from aqueous solutions containing different concentrations and different molecular weight of Polyethylene Glycol (PEG). The precipitations were analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT‐IR) and X‐ray diffraction (XRD). T…
This feature article focuses on biodoped ceramics. These are inorganic materials in which biological materials are incorporated, thus adding new functionality to them. A brief overview of the prominent synthesis techniques for biodoped ceramics, with emphasis on modified sol–gel processes for metal oxide matrices, is…
The results on the synthesis, microstructure, structure and DC magnetization studies of nanocomposite Zn,Ni ferrite/NiO powder obtained by thermal decomposition of acetylacetonato complexes are reported in this paper. According to the results obtained by inductively coupled plasma optical emission spectroscopy (ICP-OE…
The O program system and related programs are described. Topics covered include: RAVE, which is a suite of programs for electron-density map improvement and analysis; programs that interface with O for the analysis of protein models; utility programs; and internet-based services related to O and the associated program…
The authors report on ferromagnetism at room temperature in cluster-free, cobalt- and manganese-ion-implanted crystalline silicon. Through magnetic and structural analysis it is shown that the ion-implanted Si consists of two layers of Co- and Mn-containing silicon: (1) an amorphous Si layer on the surface and (2) sin…
The physical mechanism of He-ion-based exfoliation in Z-cut LiNbO3 is investigated. Rutherford backscattering/channeling, nuclear-reaction analysis, and transmission electron microscopy are used to examine the compositional and structural changes caused by deep ion implantation followed by thermal annealing. Lattice d…
Results from high-pressure synchrotron x-ray diffraction and high-temperature x-ray diffraction measurements on polycrystalline samples of the tetragonal perovskites Sr 2 GaSbO 6 , Sr 2 NiMoO 6 , and Sr 2 FeNbO 6 are reported. A phase transition, where the unit cell changes symmetry from tetragonal to cubic, is observ…
Highly oriented ZnO nanoneedle arrays were electrochemically prepared by anodization of zinc foil in a freshly prepared zincate saturated aqueous solution at room temperature. Typically, the needles have a length of 550–650 nm with a tip diameter of 10–15 nm and a root diameter of 50–60 nm, and grow along their [001]…
The authors study the electromagnetic surface waves localized at an interface separating a one-dimensional photonic crystal and left-handed metamaterial, the so-called surface Tamm states. They demonstrate that the metamaterial allows for a flexible control of the dispersion properties of surface states and can suppor…
An overview of the Rietveld method of analysing powder diffraction data, in which the crystal structure is refined by fitting the entire profile of the diffraction pattern to a calculated profile, is provided. The basic theory of Rietveld refinement is described and some problems that may lead to failure of the method…
The first section of this chapter concerns scattering factors for the diffraction of electrons by crystalline solids. An explanation of the theory of scattering by a perfect crystal is followed by a discussion of the kinematical, two-beam and phase-grating approximations. Relativistic and absorption effects are consid…
Despite the necessity of direct growth of single-walled carbon nanotubes (SWNTs) on conducting films for versatility of designing device architectures for nanoelectronics and optoelectronics, most of SWNT growths have been carried out on insulating films or supporting materials such as SiO2 and Al2O3. Here, the author…