Stability of O3 + N2, O3 + O2 and O3 + CO2 double hydrates: DFT study

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Bulk and surface electron transport in topological insulator candidate YbB6–δ

We report the study of transport and magnetic properties of the YbB_6–δsingle crystals grown by inductive zone melting. A strong disparity in the low temperature resistivity, Seebeck and Hall coefficients is established for the samples with the different level of boron deficiency. The effective parameters of the charge transport in YbB_6–δ are shown to depend on the concentration of intrinsic defects, which is estimated to range from 0.09% to 0.6%. The pronounced variation of Hall mobility μ_H found for bulk holes is induced by the decrease of transport relaxation time from τ ≈ 7.7 fs for YbB_5.994 to τ ≈ 2.2 fs for YbB_5.96. An extra contribution to conductivity from electrons with μ_H≈ –1000 cm² V^–1 s^–1 and the very low concentration n /n_Yb≈ 10^–6 discovered below 20 K for all the single crystals under investigation is suggested to arise from the surface electron states appeared in the inversion layer due to the band bending. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

Phase transitions in the ferromagnetic alloys Ni2+x Mn1−x Ga

The phase diagram of the cubic ferromagnetic shape-memory alloy Ni_2+x Mn_1−x Ga is constructed theoretically for the case when the Curie temperature is close to the structural transition temperature. This diagram agrees well with the experimental data obtained from resistance and magnetic susceptibility measurements. It is shown that the transition from the paramagnetic cubic phase to the ferromagnetic tetragonal phase can be second-order or first-order. Pis’ma Zh. éksp. Teor. Fiz. 67, No. 3, 212–216 (10 February 1998)     

Conductance Spectra of Carbyne Transverse to Carbon Chains. Is It Related to the Soliton Lattice?

The influence of the thickness of an oriented carbyne film on the conductance of a special sample was investigated with an electric field of up to 1.8 ⋅ 10⁶ V/cm applied transverse to the carbon chains. A steplike dependence of the conductance on the thickness was observed. The general shape of the current-voltage characteristics, I ∝ U ^2.3, changes to I ∝ U ² when the thickness corresponding to a rapid change of conductance is attained. The characteristics presumably correspond to the space-charge limited current in the presence or absence of the trap band within the carbyne band gap. We propose the formation of a charge-topological soliton lattice at “magic” thicknesses which results in a layered structure of the film and in a bandlike conduction transverse to the chains.     

Resistance vs. pressure of single-wall carbon nanotubes

Received: 23 January 1998     

Regular step systems on clean Si(<Emphasis Type="Italic">hhm</Emphasis>)7 × 7 surfaces

The preparation conditions and atomic structure of regular step systems on clean Si(hhm) surfaces are studied. Regular single- and triple-step structures with different periodicities have been fabricated in ultrahigh vacuum using various heat treatment procedures. The atomically resolved scanning tunneling microscopy data demonstrate several stable triple-step configurations on vicinal Si(hhm) surfaces.     

Rearrangement of defects in single crystals of cadmium sulfide irradiated with fast electrons

This study exaines CdS single crystals subjected to a special nonalloying treatment, alloyed with copper, and annealed in a cadmium atmosphere. Irradiation of the test specimens by electrons with E 1.2 MeV led to the formation of mobile defects and to decomposition of the original donor-acceptor associates. Over time, the primary radiation defects form secondary defects which act as fast recombination centers responsible for impurity photoconductivity. New donor-acceptor pairs are formed when the irradiated specimens are stored, these pairs being paramagnetic centers. Conclusions are made as to the nature of the secondary radiation defects, which are distributed both in the body of the specimens and near their surface.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 5–9, May, 1988.     

Modification of the physicomechanical properties of metallic materials by formation of nanoscale intermetallic phases under ion implantation

The fundamental and technological aspects of application of nanosized intermetallic compounds as implanted layers have been considered. The existing theoretical and experimental data on the effect of ion implantation on the structural state and physicomechanical properties of surface layers of metals (nickel and titanium) have been analyzed. The common features and differences in the phase composition and distribution of the phases formed by implantation over the alloyed metal layers are demonstrated.     

Oxidation of W(110) studied by LEED and STM

The oxidation of W(110) was studied over a temperature a range of 1000 K to 1600 K at 1 × 10^? 6 Torr oxygen. The subsequent oxide structure was then characterized using Low Energy Electron Diffraction (LEED) and Scanning Tunneling Microscopy (STM). It was found that the resulting structure was remarkably similar to that of Mo(110) oxidized under similar conditions. Using the Mo(110) oxide structure as our basis, along with atomic resolution STM images, we have constructed a model for the surface oxide of W(110).     

Use of correlation between retention indices on low-polarity phases for screening complex mixtures by gas chromatography-mass spectrometry

The reliable identification of numerous compounds in biological fluids by chromatography-mass spectrometry requires the knowledge of their retention on the phase used under specific temperature conditions. A simple method was proposed for calculating retention indices on a 5% phenyl dimethyl polysiloxane phase based on a correlation between the retention values observed for methyl- and phenyl dimethyl polysiloxane phases at different temperatures.