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。
L'étude comparative des spectres de photoélectrons X de composés de cuivre I et II, ainsi que l'examen des modifications apparaissant au niveau des raies du cuivre et de l'oxygène dans les composés de cuivre I suite à l'action de gaz actifs (O2, H2O), indiquent que la structure satellite adjacente aux raies du cuivre…
The mechanism of microhardness print forming in diamond-structure crystals is considered to be the result of a local phase transition under the indenter with the formation of a metallic phase due to the high hydrostatic pressure generated in this case. It is shown that at the temperature T < 0.3 to 0.4 Tml, where the…
The crystal structure of caesium oxotetrafluorovanadate(V) has been solved and refined to an R-value of 0.070 using diffractometer measurements. The cell dimensions are: a = 548.4(2) pm, b = 634.2(2) pm, c = 1403.4(3) pm. The space group is Pnma (No. 62) with four formula units per cell. Each vanadium atom lies 32.6 p…
The thermal and electrical conductivities of six single crystals of tin with cadmium (cadmium content ranging from 0.24 to 0.97 at.%) have been measured from 4.2 to about 80 K. The lattice thermal conductivity was deduced for three of these samples of cadmium content in excess of 0.70 at.%, oriented close to 78\ifmmod…
A neutron diffraction study of L-lysine monohydrochloride dihydrate, C6H15N202. C1.2H20, has been carried out. The structure is monoclinic, space group P2~ with Z = 2. Cell parameters are: a = 7492 (1), b = 13.320 (4), c= 5.879 (1)/~, fl= 97.79 (1) ° [Wright & Marsh, Acta Cryst. (1962), 15, 54]. Least-squares refineme…
Electron paramagnetic resonance (EPR) studies of defect centers produced by x or γ irradiation of the hydrogen-bonded ferroelectrics KH2AsO4, KD2AsO4, RbH2AsO4, RbD2AsO4, and CsH2AsO4 and of the antiferroelectrics NH4H2AsO4 and ND4D2AsO4, are presented. The spectra, observed over 300–4.2°K, are characterized by a very…
Direct near-normal-incidence reflectance spectra were measured for MnO, CoO, and NiO between 3 and 27 eV at room temperature and below, and the corresponding dielectric response functions, $\ensuremath{\epsilon}={\ensuremath{\epsilon}}_{1}+i{\ensuremath{\epsilon}}_{2}$, were obtained by Kramers-Kronig inversion. Therm…
The infrared spectra of porphin and its metal complexes with 64Zn, 68Zn, Cu, and Ni have been obtained from 4000 to 100 cm−1. Normal coordinate analyses have been carried out on the D4h model of the porphin complexes with 64Zn, 68Zn, Cu, and Ni. Only the eighteen in-plane vibrations have been calculated. The results i…
We attempt to determine the binding energy and the wave function of the ground state of an electron that is attracted to the surface of an ionic crystal by its image potential and is repelled from the interior of the solid. For ionic crystals, such as LiF, the electrostatic theory is inadequate and the solid must be t…
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…