Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
A theory of the fractional glow technique (FGT) for an arbitrary heating regime and first-order recombination kinetics is developed. In order to describe a trap distribution function (TDF) its characteristics: (i) the mean activation energy, (ii) the mean frequency factor, (iii) the recombination intensity, (iv) the F…
An experimental and theoretical investigation of the electronic structure of a ternary semiconductor, ${\mathrm{Tl}}_{3}$As${\mathrm{Se}}_{3}$, is reported. The total valence-band density of states has been measured by x-ray photoelectron spectroscopy (XPS). A simple prescription, utilizing atomic term values, is sugg…
The self-consistent-phonon (SCP) formalism has proved valuable in calculating the anharmonic contributions to lattice-dynamic properties. It is a numerical iterative procedure for obtaining the equation of state and other thermodynamic functions. Replacing the sums over frequencies in the SCP formalism by appropriate…
Dispersion relations are obtained by two different methods for surface plasmons (in the nonretarded limit) propagating on the surface of a dielectric medium on which a large-amplitude grating has been ruled. The first method is based on the Rayleigh hypothesis; the second method is based on the extinction-theorem form…
The saturation magnetization per Mn atom P s at 4.2 K was obtained with a relation P s =3.8 y µ B for y c < y <0.35 and P s =2.8 y µ B for y < y c in Mn 0.5 V 0.5- y Al y . Here y c ≈0.2 which corresponds to the concentration at the boundary between B2 and L2 1 (Heusler) structures. The 55 Mn NMR frequency at 4.2 K al…
The infrared reflectivity and transmission on the quasi-one-dimensional structure Hf${\mathrm{S}}_{3}$ of light with polarizations both parallel and perpendicular to the chains are measured. They are compared with the frequencies already observed in Raman scattering indicating that the interchain coupling is very weak.
Polarized Raman spectra of ZnCl2 were obtained in the liquid phase near the melting point (T = 598 K), and in the glassy phase (T = 293 K). Measurements were performed down to a very low frequency shift (2 cm−1) from the exciting line. Our analysis of the Raman data provides an interpretation of the collision-like con…
Optical absorption and emission spectra are reported for the cubic Cs2NaHoCl6 elpasolite system. Detailed energy and intensity analyses of the high-resolution, variable-temperature spectra allow characterization of the crystal field energy level structure associated with eleven of the Ho3+ term levels. The term levels…
Anomalous thermal expansion of FeNi alloy is calculated on the basis of Liberman-Pettifor's virial theorem and the full single site approximation in the functional integral method. Results explain well the Invar effect. In general, the electronic contribution to the thermal expansion consists of three terms, i.e. the…
Angle-resolved photoelectron spectroscopy coupled with the polarized continuum of synchrotron radiation has been used to identify unambiguously a large enhancement in the photoexcitation from A(100) due to the surface photoeffect. This large enhancement in the cross section occurs only when the excitation field has a…
A theory for the coexistence problem of the spin density wave (SDW) and superconductivity (SC) in highly anisotropic materials is presented. On the basis of a simplified electronic band model a Hartree-Fock approximation is applied. It is concluded that the SDW state is precluded when the SC state developes at a highe…
The dielectric and elastic properties of cyano-substituted nematic liquid crystals are investigated. The results are discussed in terms of molecular properties and molecular association.
Electron spin resonance signals due to isolated Zn vacancies decreased in intensity and new signals ( A 1 and A 2 ) increased as electron-irradiated ZnS containing Cl impurity was kept at room temperature. The features of the new signals are as follows: For the A 1 signal g // =2.0545 and g ⊥ =2.0264, where g // is ta…
Self-diffusion in chromium single crystals has been measured over the temperature range 1073 to 1446 K. These data, when combined with earlier measurements from this laboratory over the range 1370-2090 K, yield a plot of $\mathrm{ln}D$ vs $\frac{1}{T}$, which is straight over ten orders of magnitude in the diffusion c…
The emission and excitation spectra of the Eu3+ luminescence and the energy transfer phenomena in single crystals of Gd1−xEuxAl3B4O12 (0&lt;x?1) have been investigated using time-resolved site-selection techniques. In addition, the luminescence properties of single crystals and powders have been compared. The resu…
Enhancement of the Raman scattering and fluorescence emission on noble metals (Ag, Cu, and Au) is believed to be caused in part by large local fields at the incident wavelength on the surface of metallic microstructures, such as colloidal suspensions and surface roughness on electrodes and thin films. For metallic sph…
Potassium acid phthalate (COOKC 6 H 4 COOH) single crystals were grown from aqueous solutions. The cleavage surfaces were examined by multiple-beam interferometry. Solvent etching was used to delineate the dislocations, and their distribution and branching were investigated. The (001), (010) and (100) faces were subje…
The author considers a polycrystal composed of crystallites for which the response to a hydrostatic pressure is a pure dilatation. Cubic crystals have this property, but it might also be possessed by crystals of lower symmetry. It is proved that the polycrystal also has this property and, regardless of the distributio…
We report what we believe is the first experimental measurement of biaxiality in a cholesteric phase. This observation is made in a selectively deuterated nematic that was twisted by the addition of a chiral compound. A theoretically predicted biaxial order parameter (measured in terms of an asymmetry in the time-aver…
Abstract Radiochemical oxidation of Mn2(μ-AsPh2)2(CO)8 in Freon mixture glass gives its cation radical, ESR spectra of which are most consistent with the odd electron orbital with σ*MnMn character consisting mainly of Mn 3d and As 4p atomic orbitals.