Showing papers in "Journal of Physics and Chemistry of Solids in 1979"

TL;DR: In this article, the ESR signals from oxidized, single-crystal TiO2 undoped and doped with V, Cr, Mn or Fe were made both before and after exposure to white light from a tungsten lamp; they revealed a band of states centered at 2.0 eV below the conduction-band edge.

TL;DR: In this paper, the length change of a 25mm long single crystal of NaCl has been determined as a function of hydrostatic pressure up to 32 kbar and temperatures up to 500°C using an electrical contact piezometer with tungsten carbide as a standard.

TL;DR: In this article, the single crystal elastic constants of aluminum have been measured using a piezoelectric composite oscillator from room temperature to just 20 K below the melting point, and the elastic moduli differ markedly from previous high temperature results, but match in well with previous cryogenic results.

TL;DR: In this article, the dominant disorder in GaAs is Frenkel defect formation on the arsenic sub-lattice with the arsenic vacancy exhibiting donor-like behaviour at high temperatures, and the phase extent of GaAs was mapped and the model shown to account adequately for the density, lattice parameter and internal friction variations in as-grown and heat treated material as well as for the high temperature Hall coefficient behaviour.

TL;DR: In this article, a detailed study of the effects of temperature and hydrostatic pressure on the ionic conductivity of PbF 2 in both the cubic (Fm3m-O h 5 ) and orthorhombic (Pmnb-V 2 h 16 ) phases was performed with some emphasis on the changes in conductivity accompanying the transition between two phases.

TL;DR: Mossbauer and magnetic susceptibility studies of sixty tetragonal RM 4 Al 8 compounds (R = 4 f, M = 3 d element), show a wide variety of magnetic phenomena in the behaviour of 3 d transition elements.

TL;DR: A microscopic interstitialcy-type diffusion mechanism for sodium β-alumina involving three crystallographically different types of cation sites but only two equilibrium configurations of interstitialy pairs is proposed in this paper.

TL;DR: In this paper, a model based on the coexistence of two types of defects, namely, vacancies in the lithium sub-lattice and lithium antistructure atoms in the aluminum sublattices, characterized the defect structure.

TL;DR: In this paper, the effect of the lighting configuration on spectral PV plots is discussed, and the origin of two peaks of PV responses is interpreted as being in accordance with optical data.

TL;DR: In this paper, the phase diagram of thermally depoled tetragonal PLZT materials has been investigated by means of X-ray diffraction, Capacitance and DSC measurements.

TL;DR: The point defect model described in the companion paper is used to construct solubility relations, predict the effects of heat treatment and account for the large lattice dilations in tellurium doped GaAs as discussed by the authors.

TL;DR: In this article, the free energies of the spinel phases as functions of composition and temperature are derived and the analysis of the phase equilibria are greatly facilitated through the use of isothermal log PO2-composition phase diagrams.

TL;DR: In this article, values of dC/dT)V have been computed from experimental measurements of the three elastic constants (expressed as B T, C 44 and (C 11 −C 12 ) 2) of each of the 16 Li, Na, K, and Rb halides.

TL;DR: In this paper, tracer diffusion and ionic conductivity were measured on the same single crystals of sodium beta-alumina of composition 1.23 Na20.11 Al2O3.

TL;DR: In this article, a latent heat effect is observed at the sharp FEt → PEc transition in PLZT x/30/70 materials with a low La content (x <16 at° La).

TL;DR: In this article, the authors calculated the formation entropy for the migration process of rare earth fluorides doped with trivalent rare earths and showed that it is a bulk property of the matrix material.

TL;DR: In this article, the interaction of oxygen with Cu(100) surfaces was investigated from 85 to 800 K by AES, ELS, LEED and work function change, and three different states of oxygen bonding were observed.

TL;DR: In this paper, single crystals of Bi 2 Sn 2 O 7 were grown in a Bi 2 O 3 flux and phase transitions were identified at about 90 and 680° using X-ray, SHG, DSC, dielectric, and optical data.

TL;DR: In this paper, the principal complex dielectric constants have been studied at audio frequencies over the temperature range 5.5-380K for α-quartz, sapphire, magnesium fluoride, and calcite.

TL;DR: In this article, the Lagrangian strain tensor and the frame-indifferent analogue of the Eulerian tensor are derived for a material of orthorhombic symmetry under hydrostatic stress, and three generalized Gruneisen parameters relative respectively to the three principal directions of the deformation can be defined.

TL;DR: In this article, the authors measured the capacity of VHn and NbHn with n up to 1.93 at temperatures between 1.5 and 16 K and showed that the two-phase region presumably extends up to n ≈ 0.9 at helium temperatures.

TL;DR: Theoretical methods based on Mott-Littleton techniques are used to investigate the defect structures of alkali-halide crystals doped with divalent ions in this article.

TL;DR: In this paper, the spectral lineshape of a NbH 0.02 single crystal has been measured for a wavevector transfer Q between 0.5 ≤ |Q| ≤ 2.

TL;DR: In this article, the authors measured the temperature changes associated with adiabatic pressure changes ( ∂T / ∂P ) s for sodium and potassium at room temperature (297 K) under hydrostatic pressures up to 32 kbar.

TL;DR: In this article, the Arrhenius relation was used to measure the temperature dependence of the diffusivity of hydrogen in platinum in the temperature range 558-936°C.

TL;DR: In this article, the electronic structure of actinide monoxides and dioxides has been studied in spin-restricted and spinpolarized models using the discrete variational method with numerical atomic basis functions.

TL;DR: In this paper, sound velocities have been measured in polycrystalline silver iodide at pressures up to 1 GN m 2 and temperatures up to 425 K. The measurements covered the P - T ranges of three polymorphs of AgI but the main phase of interest was the B1 phase stable at high pressures.