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The results of measurements of electronic conductivity and the Seebeck coefficient, as well as X-ray phase analysis, electron microscopy, differential scanning calorimetry (DSC) and studies of the heat capacity of nanocrystalline NaxCu2-xS (x = 0.05, 0.075, 0.10) and Na0.125Cu1.75S semiconducting alloys in the temperature interval of 300 - 600 K are presented. At ambient temperature, the alloys under study consist of three phases: monoclinic Na2Cu4S3, hexagonal Chalcocite Cu2S and rhombohedral digenite Cu9S5. Measurements show that the Seebeck coefficient increases, and the conductivity decreases with increasing sodium concentration in the alloys. Thermal effects near the temperatures of 360 K, 450 K and 640 K have been observed by the DSC method.

The paper is focused on the study of the structural, electrical and optical characteristics of the ceramic silicon carbide before and after irradiation in the regimes of the high-power ion beams (HPIB) and high-intensity short-pulse implantation (HISPI) of carbon ions. The dominant mechanism of transport of charge carriers, their type and the energy spectrum of localized states (LS) of defects determining the properties of SiC were established. Electrical and optical characteristics of ceramic before and after irradiation are determined by the biographical and radiation defects whose band gap (BG) energy levels have a continuous energetic distribution. A dominant p-type activation component of conduction with participation of shallow acceptor levels 0.05-0.16 eV is complemented by hopping mechanism of conduction involving the defects LS with a density of 1.2T0{17}-2.4T0{18} eV{-}Am{-3} distributed near the Fermi level.The effect of radiation defects with deep levels in the BG on properties change dominates after HISPI. A new material with the changed electronic structure and properties is formed in the near surface layer of SiC after the impact of the HPIB.

This paper presents new experimental data on the total cross sections of 9Li + 28Si reactions at low energies as well as the analysis of previously obtained data for 6,7Li. Based on a large collection of data (authors' and literature data) we carried out a comparative analysis of the two main experimental interaction cross sections (angular distributions of the differential cross sections and total reaction cross sections) for weakly bound lithium (6-9Li, 11Li) nuclei in the framework of Kox parameterization and the macroscopic optical model. We identified specific features of these interactions and predicted the experimental trend in the total reaction cross sections for Li isotopes at energies close to the Coulomb barrier.

Electrophysical properties of polycrystalline diamond films (PDF), deposited from the abnormal glow discharge, were obtained. The energetic and kinetic characteristics of surface dark and photoconductivity of PDF and their temperature, field and spectral dependences were investigated. Dominant carrier transport mechanisms, their type and the energetic spectrum of localized defect states were established. Current-voltage characteristics, photosensitivity and activation energy are determined by conductivity of PDF, which varies from 10{-14} to 10{-4} S depending on deposition conditions. Vacuum annealing of films up to 600-800 K stabilizes the electrical characteristics. Thermal stability of PDF properties higher than semiconductor films, deposited under nonequilibrium conditions by pulsed laser and ion ablation. PDF films not inferior on properties to films, obtained by alternative CVD methods. Electrical characteristics, mechanism of charge transport of PDF were caused by defects of different nature, the energetic levels of which are continuously distributed on energy in the band gap. Dominant n-type of activation conduction is complemented by hopping mechanism through the localized states distributed near the Fermi level with density 5.6x10{17}-2.1x10{21} eV{-1} cm{-3}. Trapping and recombination centers are heterogeneously distributed on grain boundaries.

The optical and electrophysical properties of polycrystalline diamond films (PDF) deposited from the abnormal glow discharge have been studied. The dominating mechanisms of absorption and charge carrier transfer and the energy spectrum of the localized states (LS) of defects which determine the properties of the films have been specified. The parameters of the interband absorption and electrical conductivity are determined by the continuous energy distribution in the band gap (BG) of the states of defects of different nature. The absorption edge of the crystalline phase of the films is separated from the absorption zone determined by the electron transitions between LS defects. The width of BG is narrowed to 0.2-0.5 eV from the quantity typical to the diamond. An additional film absorption edge is formed in the energy interval 1.2-3.3 eV, where Urbach rule is fulfilled and the interband absorption is realized at direct transitions through the optical gap 1.1-1.5 eV. The average width of BG is 2.6-3.24 eV estimated within semiclassical interband model. The interaction of the parameters of the interband and exponential absorption is determined by the crystal lattice static disorder. The dominating n-type of the activation component of the electrical conductivity is complemented by the hopping mechanism with the participation of the localized states of the defects distributed near the Fermi level with a density 5.6•10{17}-2.1•10{21} eV{-1}•cm{-3}.

The characteristics of interband and exponential optical absorption of leucosapphire and polycrystalline corundum (polycor) after irradiation with chromium ions and subsequent annealing in vacuum at 300-1800 K and in air at 300-800 K are studied. Contributions of defects with different thermal and chemical stability into optical parameters were established. The effect of intrinsic radiation defects, of substitutional defects and of complexes on base of oxygen and defects on formation the focal point in absorption spectra owing to fulfilment of the Urbach rule was determined. Heating in air of strongly defective material synthesized in surface layers of alumina by the ion-heat modification influences the characteristics of defects and the electronic structure of band gap negligibly.

Electrical and photovoltaic properties of polycrystalline diamond films (PDF), deposited from the abnormal glow discharge were analysed. Features of charge carrier transfer in PDF are determined by continuous energy distribution in the band gap of defect states of different nature. Dominated n-type conductivity activation component of electrical conduction and photoconductivity is complemented by a hopping mechanism with the participation of states near the Fermi level with a density 5.61017–2.11021 eV−1 cm−3. Activation transfer is realized in the exchange of charge carriers between the allowed bands and donor levels with the activation energy 0.007-0.21 eV, which are sparsely populated and have wide variation in their parameters. Trapping centers and carriers recombination are heterogeneously distributed in grain boundaries. Under lighting, the state density increases 3-5 times and probable jump length decreases by 1-3 nm. Spectral distribution centers of photosensitivity are correlated with the distribution of deep-level defects, determining the absorption spectra.

Electrophysical and photoelectric properties of thin GaAs films deposited on polysilicon by pulse ion ablation using high-power ion beams have been investigated. The predominant charge carriers transfer mechanism in films and the type of dark and photoconductivity have been established. A vacuum annealing effect (10−2 Pa, 300-1000 K) on energetic and kinetic characteristics of dark and photoconductivity, the transfer mechanism and the type of charge carriers have been determined. The most probable causes of changes in the film electric and photoelectric characteristics have been discussed.