Showing papers in "Journal of Physics and Chemistry of Solids in 1982"

TL;DR: The mpx3 phases (M = Mn, Fe, Ni; X = S, Se) with sheet structures are insulators with localized moments and show antiferromagnetic ordering at low temperatures as discussed by the authors.

TL;DR: In this article, the structural properties of Prx 1− x Ca x MnO 3 perovskite systems were studied by X-ray and magnetic susceptibility measurements, and the results are interpreted as being due to simultaneous action of steric effect, orbit-lattice interactions of Mn 3+ ions and Coulomb interactions among 3 d electrons.

TL;DR: In this article, an investigation of the Schottky barrier of a number of metals on natural P-type MoS 2 was undertaken, and the spectral dependence of the photovoltaic effect of all the metal barriers showed two distinct features at 1.38 and 1.68 eV below the direct bandgap at 2.8 eV.

TL;DR: In this paper, a numerical method to treat diffusional reactions in alloys where a thermodynamic description, complete enough to represent phase equilibria, as well as diffusion coefficients is available.

TL;DR: In this paper, the authors used the amorphous soap bubble raft as a two-dimensional analog medium that can give quantitatively accurate simulations of both the structural properties of metallic glasses and the mechanisms of their inelastic deformation.

TL;DR: In this paper, a phenomenological approach and some physical models are applied to phase diffusion in multicomponent alloys in order to extend earlier treatments to phases with sublattices.

TL;DR: In this paper, the authors studied the ionic conductivity of the AgBrAgI system as a function of composition and temperature, and they obtained the maximum conductivity 3 × 10 -4 Ω −1 cm −1 at 25°C, which is $ 3 orders of magnitude larger than that predicted by the classical theories of Lord Rayleigh and Maxwell.

TL;DR: In this article, the authors investigated the IR spectra of OH-compensated point defects in MgO (and CaO) single crystals of various purity grades and assigned three distinct groups of IR bands: band A to the fully compensated, band B to the half compensated and band C to the over compensated cation vacancies.

TL;DR: In this paper, the isotope effect for self-diffusion was measured by simultaneous diffusion of 52 Mn and 54 Mn in Mn 1−δ O (0.0004 f ΔK).

TL;DR: In this paper, a neutron diffraction study was performed on (Bi2O3)O. The authors concluded from diffuse scattering that at low temperatures short-range ordering appears, leading to the occurrence of relatively short Ln-O distances.

TL;DR: In this paper, the preresonance and resonance Raman spectra of solid films of metal-free phthalocyanine have been studied and a vibrational description of prominent spectral features is given in terms of the macrocycle (inner ring) and isoindole moieties.

TL;DR: In this paper, the authors investigated the luminescence properties of TbAl 3 B 4 O 12 in the temperature region 1.4-300 K and showed that energy migration among Tb 3+ ions on the regular crystallographic sites occurs.

TL;DR: In this paper, the formation energies for the point defect species Ti4+ interstitials, Tii4+, and oxygen vacancies with an effective charge of + 2e, Vo2+, have been calculated using the polarisable point ion shell model.

TL;DR: By analyzing the electrical conductivity at constant thermoelectric coefficient, the small polaron conduction mechanism can sometimes be unambiguously established in transition metal oxides as discussed by the authors, and the data for Co 1−δ O indicate band-type conduction.

TL;DR: In this paper, Fick's diffusion coefficients for hydrogen and deuterium were determined in palladium hydride, and an electrical resistance relaxation method was used experimentally to interpret the anomalous behavior of the diffusion coefficient in the low temperature range.

TL;DR: In this paper, the authors considered the crystal structure of NbO as a NaCl structure with 25% ordered vacancies in each sublattice and found that the introduction of the vacancies leads to a lowering of the Nb- d like bands with respect to the O- p bands, an almost completely filled "vacancy band" and a splitting and broadening of the O - p like band.

TL;DR: In this paper, the authors measured the permeability and diffusivity of hydrogen in molybdenum using the time-lag method using MEM membranes prepared by electron beam melting and cleaned by argon ion etching.

TL;DR: Using the 12 C d, p ) 13 C method and ultrahigh vacuum techniques, it was shown that MgO single crystals, grown by arc fusion, invariably contain high concentrations of carbon, 250-2500 at.-ppm as mentioned in this paper.

TL;DR: The optical absorption and ESR spectra of Bi 12 GeO 20 and B 12 SiO 20 doped with Mn have been measured before and after illumination with visible light as discussed by the authors.

TL;DR: In this paper, four types of center transformation processes enhanced by photoexcitation are given consideration: (1) Association of shallow donors with one another, (2) Dissociation of donor-acceptor pairs (DAP), (3) Donor migration from dislocations into the bulk of the crystal and association with acceptors, (4) dissociation of complexes, consisting of several DAP and deep acceptors.

TL;DR: In this paper, the a.c., d.c. and d.d. electrical conductivity and thermoelectric power of a single crystal of MnWO4 were reported in the temperature range 300-1200 K. The data have been analyzed using the polaronic concept of electrical conduction.

TL;DR: In this paper, the structure and magnetic properties of TlCrX2 (X= S, Se, Te), Tl3CrS3, TlCl5S8 and AgCrO2 have been investigated.

TL;DR: In this paper, the structure of the lithium inserted rutile-based compound LiMoO2 has been determined from neutron powder diffraction data by use of the Rietveld profile technique.

TL;DR: In this paper, the electrical properties of HgTe and HgSe were investigated at pressures up to 200 kbar in an octahedral apparatus, and the energy gap at various fixed pressures was obtained from the resistance-temperature relationships.

TL;DR: In this paper, a Monte Carlo model is used to simulate the thermodynamic equilibrium of a substitutional binary f.c. solid solution with pairwise interactions, which is used for the determination of ground state structures, the calculation of short-range and long-range order data at non-zero temperatures, and the computation of the uppermost ordering temperatures.

TL;DR: In this paper, the aggregation and precipitation behavior of lead in NaCl and KCl crystals has been systematically investigated by absorption and luminescence spectroscopy, and the emission spectra for excitation at those absorption bands have also been determined.

TL;DR: In this article, the Raman spectrum of crystalline As 4 S 3 has been investigated as a function of temperature from 4 to 430 K at ambient pressure, and at a level of pressure to 70 kbar at ambient temperature.

TL;DR: In this paper, the mechanisms of cis-trans irreversible isomerization occurring in both thermal treatment and doping of polyacetylene are presented and examined by means of MINDO/3 molecular orbital calculations on some finite polyenes.

TL;DR: In this paper, a study of electronic conductivity using the d.c. polarization technique has been carried out in α and β-AgI which shows the former is a hole and the latter an electron conductor.