Materials Literature
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The Rayleigh–Brillouin spectrum of 2,4-dimethyl pentane, 2,4,6-trimethyl heptane, 3,5-dimethyl heptane, 2,2,4,4-tetramethyl pentane, and 2,2,4,4,6,6,8,8-octamethyl nonane was measured as a function of temperature from well above the Brillouin linewidth maximum down to the glass transition region. Brillouin splittings…
We report on high-resolution total-yield measurements of the Cu ${L}_{2,3}$ absorption edge in ${\mathrm{Cu}}_{2}$O using the JUMBO monochromator at the Stanford Synchrotron Radiation Laboratory. Care was taken to prepare the surface of a well-characterized single crystal, rather than use oxidized copper. A comparison…
Angle-resolved photoemission with synchrotron radiation was applied to Pb(111) in order to determine the electronic band structure of Pb. The $\ensuremath{\Gamma}L$ direction was mapped out by recording normal-emission photoelectron spectra. Band energies at several symmetry points in the Brillouin zone were obtained…
A gradient-index antireflection coating spanning the 0.6–12.6-μm wavelength range for a ZnSe substrate was designed, fabricated, and tested. The index profile used was a fifth-order polynominal that smoothly matches the substrate. The coating was fabricated using a discrete layer approximation for the gradient-index d…
We report theoretical investigations on the electronic structure of ideal, defect-free surfaces of rutile (${\mathrm{TiO}}_{2}$). The (110), (001), and (100) faces are studied, and for each face, several models are examined, which correspond to different surface atomic compositions. The bulk electronic structure is de…
The diffusion of As in polycrystalline silicon films subjected to rapid thermal annealing has been studied using sheet resistance and Rutherford backscattering. The polycrystalline Si films were deposited on oxidized silicon wafers, implanted with As, and annealed with a Varian IA-200 isothermal annealer. Infrared rad…
Soft-x-ray emission ($K\ensuremath{\beta}$ emission) and absorption ($K$ absorption) spectra of a black P single crystal polarized along each crystalline axis are presented for the first time. The experimental results indicate (1) the upper part of the valence band near the Fermi level is largely contributed by the $3…
The electron density distribution in Fe–phthalocyanine is mapped using a set of accurate diffraction data collected at 110 K. Structural results are in agreement with an earlier room-temperature determination. Deformation electron density maps show a deficiency of the Fe electron density along the axis perpendicular t…
The character of the first unoccupied band in the graphite intercalation compound ${\mathrm{LiC}}_{6}$ is examined. Based on a framework of interacting nonorthogonal states, an analysis of previous band-structure results shows that this band can be interpreted as a hybrid of Li $2s$ and graphite interlayer states.
The temperature dependence of the birefringence and magnetic field induced effects were studied on thin films of mixtures of potassium laurate, 1-decanol, and D2O. The selected mixtures have a small biaxial nematic range between two uniaxial nematics. The biaxial–uniaxial nematic phase transitions are second order and…
Reflectivity measurements in the far-infrared region irrefutably show the consequence of the Peierls instability in the blue bronze ${\mathrm{K}}_{0.3}$${\mathrm{MoO}}_{3}$ system. At 5 K, a very strong polarization-dependent phonon spectrum is observed: At photon energies below 8 meV, a giant, nearly undamped structu…
Measurements of the frequency, temperature, and isotope-mass dependence of the electrical conductivity in a series of ${(^{6}\mathrm{Li},\phantom{\rule{0ex}{0ex}}^{7}\mathrm{Li})}_{2}$ O:2.${88\mathrm{B}}_{2}$${\mathrm{O}}_{3}$ glasses are quantitatively described by a unified model of relaxation. The data simultaneou…
Room-temperature values of the thermal conductivity ($\ensuremath{\kappa}$) of pure and heavily doped polyacetylene, both cis and trans isomers, have been experimentally determined using a new experimental approach for the determination of $\ensuremath{\kappa}$ along the plane of the sample. We find that effects of ra…
The nearest-neighbor distances around Te atoms in the random semiconducting alloy ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$ have been determined by the extended x-ray-absorption fine-structure technique. The distribution of the anion-cation distances is bimodal. A model of the microscopic structur…
Franco et al. has shown the inhibi tion of ferroelectric swi tching I when TGS crystals are treated during 1000 hours with an electric potential.In order to determine whether the inhibition may be explained in terms of the structure, we have determined the crystal structure of a swi tehing fatigued crystal.The results…
possible errors in the input data.A systematic survey of structures in the Inorganic Crystal Structure Database shows that the program can provide a proper description of the chemical bonding for about 90%
scaLLering faeLor of Pb and Bi aLom aL sinBIA = 0.0 is enlarged La 3.2.A seL of 237 inLensiLy of hkO refleclions(including 37 sLandard reflections) was collected with the .CJ~28 step scan mode, using a four-circle diffractomeLer seL up aL Lhe BL-IOA sLation.AfLer correction of dead time of detector system, Lorentz fac…
Abstract Certain ternary metal oxides release oxygen at their surfaces when they function as catalysts for the selective oxidation of hydrocarbons. In so doing, they become non-stoichiometric, often quite markedly so (up to x = 0.5 in AMO3-x). In perovskite related phases of this kind, oxygen from the gas phase is rea…
Abstract Flexural stress relaxations were measured for rigid polyurethane foams (PUF) and glass‐fiber‐reinforced rigid polyurethane foams (FRU). The results were successfully analyzed in terms of the five element Maxwell model: (1) Samples reinforced with longer fibers exhibit reduced stress relaxation and reduced tem…
Several new fluorene derivatives have been synthesized and their liquid crystalline polymorphic behavior examined. Specifically, 2-fluorenylmethylidene-4′-n-alkylanilines with different alkyl groups are compared with corresponding compounds wherein the alkyl groups have been replaced either by the alkoxy or other diff…