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。
X-ray photoelectron spectroscopy (XPS) and tight-binding calculations are used to study the electronic structure and the local order in ${\mathrm{Ge}}_{\mathrm{x}}$${\mathrm{Se}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$ glasses (0<x<0.42). The shape of the valence electronic density of states in Ge-Se compounds is…
Molecular-dynamics simulations are employed in studies of liquid-phase epitaxial growth onto a Si(111) surface. The material is described using two- and three-body interaction potentials which provide a realistic description of crystalline silicon and of the crystal-melt interface. From equilibrium solid-melt coexiste…
Electrochromic properties of nickel-oxide films have been investigated. Films were prepared by rf sputtering from a compressed powder NiO target in an atmosphere of an Ar-O2 mixture. The deposition rate of the nickel oxide decreased when the total pressure of the sputtering atmosphere was increased, but was independen…
Angle-resolved inverse photoemission spectroscopy (ARIPES) and angle-resolved secondary-electron emission spectroscopy (ARSEES) have been performed for graphite to establish experimentally the unoccupied-electronic-band structure as well as to study the difference between the two techniques. Remarkable differences hav…
An upper critical field measurement in the recently discovered ambient pressure organic superconductor (BEDT-TTF) 2 Cu(NCS) 2 ( T c =10.4K) is reported. Three- to two-dimensional crossover behaviour is observed in the temperature dependence of the parallel critical field. The anisotropy of the coherence length near T…
A theory of both thermal and quenched diffuse scattering from incommensurate crystals and quasicrystals is developed. We explore, in particular, the effects of strain fluctuations due to phasons which have dropped out of equilibrium at high temperatures, providing a source of quenched, spatially varying disorder. The…
Molecular-dynamics simulations of amorphous silicon are described, using the two- and three-body interaction potentials constructed by Stillinger and Weber. The amorphous-material preparation procedure is described and the structural and dynamical properties of the amorphous phase are simulated and analyzed. The chara…
Three very long runs of constant temperature molecular dynamics (MD) simulations, extending over typically 2×105 time steps, have been carried out for a state just above the glass transition of equimolar soft-sphere mixtures, with 500 atoms interacting through vαβ(r) =ε(σαβ /r)12, where σαβ =(σα +σβ )/2, and α,β (spec…
We study a one-dimensional system which is neither periodic, quasiperiodic, nor random. We find that the structure factor of this system consists of a set of peaks whose heights scale with L, the length of the chain, according to ${L}^{\ensuremath{\alpha}(k)}$. We show that for k(1/2, \ensuremath{\alpha}(k)\ensuremath…
A single-crystal charge–transfer complex of a phenyl-end-capped tetramer of polyaniline has been synthesized and studied along with a similar dimer of polyaniline. Structural, optical, and electrochemical studies of these oligomers in various oxidation states provide detailed information which has been used to model t…
The electronic structure and magnetic properties of Mn-substituted II-VI diluted magnetic semiconductors are treated theoretically with emphasis on ${\mathrm{Cd}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Mn}}_{\mathrm{x}}$Te. The derived electronic structure is based on a combination of ab initio spin-polarized…
RETM5 and RE2TM17 (RE=rare earth, TM=transition metal) permanent magnets are discussed in this review. The scientific and technological considerations which have guided their development are described. Along with a discussion of the various research efforts reported in the literature, they help establish the framework…
Electrical resistivity and Hall effect coefficient measurements have been made on MnSi 1.73 thin films in the temperature range 100 to 850 K. The temperature dependence of resistivity shows the typical behaviour of a degenerate semiconductor. The energy gap calculated from resistivity and Hall effect data is about 0.4…
We present neutron-spin-echo results on the dynamics of crosslinks in a tetrafunctional model network of polydimethylsiloxane. The diffusive motion was found to be rouse type and restricted in space. For the first time the extent of these spatial limitations was determined experimentally. The results strongly support…
We have been able to observe the enhanced Raman scattering from copper phthalocyanine molecules deposited on layers of gas-evaporated GaP small particles. It is found that the enhancement factor increases as the average particle size increases; a maximum enhancement factor obtained in the size range between 400 and 11…
The one-dimensional, discrete Schr\"odinger equation is studied when the potential is allowed to take on two values, ${V}_{A}$ and ${V}_{B}$, which are arranged according to a generalized Fibonacci sequence. The problem is reduced to a dynamical map for the traces of the transfer matrices which are given recursively b…
This article presents a variational approach for calculation of the dynamic third-order susceptibility χ(3). The susceptibility is obtained directly through a solution of two sets of inhomogeneous linear equations.
Photoluminescence in the GR1 zero-phonon region has been examined in detail, using a tunable dye laser resonant with the higher excited states GR2 to GR8. The authors conclude that the temperature-dependent structure observed when electron beam excitation is used is not due to perturbation of the centre resulting from…
The Raman spectra of single-crystal Co 3 O 4 have been measured at 312 K. Five Raman-active modes were found and identified at 194, 482, 522, 618 and 691 cm -1 .
The loss of the antioxidants BHA and BHT from HDPE film was measured experimentally and analyzed theoretically. The volatilization of the antioxidant from the polymer surface was found to be the controlling parameter for mass transfer. Diffusion coefficients of the antioxidants evaluated from the experimental data and…