Materials Literature
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A simple device for use with open shell SCF computations is proposed. This method eliminates the nonphysical elements in the usual method and leaves a simple operator which is easily computed or approximated.
A detailed experimental and theoretical study of the defect-induced far-infrared and first-order-Raman spectra of the NaCl: ${\mathrm{Ag}}^{+}$ system has been made. New low-temperature Raman data revealed many singularities pertaining to pure and perturbed phonons. Only a few of the singularities could be assigned to…
The first observation of surface-phonon-surface-plasmon coupling in small particles is reported. Thin layers of semiconducting CdO microcrystals with various free-carrier concentrations were used as samples. The coupling manifests itself in the infrared-absorption spectra through two absorption maxima corresponding to…
The cubic pyrochlores Cd 2 Nb 2 O 7 , Cd 2 Ta 2 O 7 , Sn 2 Nb 2 O 7 , Sn 2 Ta 2 O 7 . Cd 2 Sb 7 O 7 , Ca 2 Sb 2 O 7 , Mn 2 Sb 2 O 7 , Pb 2 Sb 2 O 7 , and related compounds were prepared and investigated by a number of methods. On heating above 700°. Ca 2 Sb 2 O 7 (pyrochlore) transformed to Ca 2 Sb 2 O 7 (weberite), w…
The crystal structure of trehalose dihydrate has been solved by direct methods and refined to an R index of 0-057 using anisotropic refinement. The space group is P212121 and four formula units of C12HzzOz~.2HzO are contained in the unit cell of dimensions a= 17.90, b= 12.21 and c= 7.586 A. The two glucopyranose resid…
We have used the second harmonic of a Nd: glass laser and a continuously tunable dye laser to measure the variation of the third-order nonlinear susceptibility ${|{\ensuremath{\chi}}^{(3)}(\ensuremath{-}2{\ensuremath{\omega}}_{1}+{\ensuremath{\omega}}_{2}, {\ensuremath{\omega}}_{1}, {\ensuremath{\omega}}_{1}, \ensurem…
The thermal conductivities $\ensuremath{\kappa}$ of over twenty different single crystals of synthetic ZnO, ZnS, ZnSe, ZnTe, CdTe, and of natural, cubic ZnS have been measured from temperatures of 3 to 300 K. The results for the undoped crystals above 30 K can be scaled using the parameter $\overline{M}\ensuremath{\de…
The lowest conduction bands of a number of perovskites are determined principally by the ($\mathrm{pd}\ensuremath{\pi}$) interaction which mixes the ${t}_{2g} d$ orbitals of the transition-metal ion with the $p$ orbitals of the oxygen. Because of the planar character of the ($\mathrm{pd}\ensuremath{\pi}$) interaction,…
We present a method for the conversion of x-ray diffraction data into an electron density which reflects the antisymmetry of the N-electron wave function.Received 24 January 1972DOI:https://doi.org/10.1103/PhysRevLett.29.1363©1972 American Physical Society
Accurate birefringence measurements on monodomain SrTi${\mathrm{O}}_{3}$ platelets give important information about the fluctuations associated with the second-order structural phase transition. Above the transition, the monodomain character is announced by a birefringence tail caused by anisotropic fluctuations. Beca…
The adsorption of elemental mercury vapor on a thin (several hundred angstroms) gold film produces resistance changes in the film. An instrument for the detection of mercury based on this phenomenon is simple and rapid and requires no chemical separations other than passage of the vapor sample through a few standard d…
Abstract The height of a sessile drop first increases as the drop size increases and then diminishes to a limiting value for very large drops. The variation of sessile drop height with drop size has been calculated and is given in graphical form for a very wide range of drop size and of contact angle. These data are t…
The author criticizes the shortcomings of the usual text book explanations of surface tension and capillary rise which are two quite different types of phenomena.
Abstract The thermal degradation of saturated chlorinated polyethylene in powder and fiber form has been studied. Direct observations of fiber length variations have enabled us to prove the reactional mechanisms proposed. In the temperature range of 200°–300°C, the material exhibits some fluidity. Its degradation is e…
Abstract An activation energy theory of yielding in glassy polymers has been proposed by Starita and Keaton. It predicts a linear relation between energy to yield and test temperature. This concept was tested and found valid for five amorphous polymers; poly(methyl methacrylate), polycarbonate, polyarylsulfone, polysu…
Stacking faults nucleated at an annealing twin boundary in pure nickel are analysed by electron microscopy. The formation of the stacking faults is qualitatively explained in terms of the forces acting on the partial dislocations in the annealing twin boundary and in the matrix. The critical factors are found to be th…
Abstract Zusammenfassung . Es wird die Synthese der im Titel genannten 3‐Amino‐cardenolide beschrieben.
The phase diagram of water at moderate pressures is studied by a dielectric measurement for solid-solid transitions and further by a volume change method for liquid-ice VI transition. The metastable phase ice IV can be made from ice VI on decreasing the pressure at temperatures from -13.6 to -14.6°C. The growth and th…
Abstract It is shown by ESR‐measurements on differently treated single crystals of MoO 3 that in these crystals the localisation of molybdenum 4d 1 electrons is always connected with the presence of protons. We determine the parameters of the transferred hyperfine interaction tensor.
Abstract Polyethylenimine (PEI) has been oxidized with aqueous hydrogen peroxide to yield a hygroscopic, water‐soluble, slightly basic, yellow polymeric solid (OPEI) containing about 25% oxygen. Some chain degradation accompanies oxidation. The nature of the product varies somewhat with preparative conditions. OPEI, i…