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The IR spectra of CDF3 in the solid Ar and N2 matrices were measured and analyzed in the region of the Fermi polyads 2ν4/ν1/2ν2/ν4 + ν5, complicated by a close Fermi resonance ν4/ν3 + ν6. The symmetry lifting effect, observed in the N2 matrix, was found helpful for an accurate assignment of the individual components. The anharmonic calculation of the potential energy surface and the dipole moment function was performed on the MP2/aug-cc-pVTZ level. The unperturbed values of vibrational eigenstates were determined in the region of ν1 (CD stretching vibration) in both matrices. The experimental findings and theoretical analysis are in good agreement. [ABSTRACT FROM AUTHOR]

Research findings can offer data and a theoretical framework for a quantitative examination of the bentonite dehydration mechanism. The reasons for changes in pore’ water under the influence of gamma rays in vacuum and in the presence of oxygen was discussed using TGA and DTA, FT-IR spectroscopy. It was revealed that dehydration and pore characteristics are mutually dependent. A question about the associated evolution of dehydration pore‘s water in nanostructured sodium – bentonite clay under the influence of ionizing rays with and without oxygen has been comparatively studied. The article is devoted to a discussion of how ionizing radiation, passing through nanoclays, produces, or rather begins to produce, chemical effects. It was used Infrared spectroscopy as the method for determining structural responses of natural clay from the Alpoid deposit in the Republic of Azerbaijan, to gamma rays exposure. It was found that under influence of ionizing rays in vacuum obtained hydrogen peroxide. It is of great interest for the study of the dehydration reaction mechanism and its role in formation of H2 under gamma irradiation. [ABSTRACT FROM AUTHOR]

In the present investigation, pure and different concentrations (2%, 4%, 6%, 10%) of Ag-doped Co3O4 nanoparticles have been synthesized by the sonochemical method and subsequent calcination at different high temperatures. Structural, optical, morphological properties and elemental composition of synthesized nanoparticles have been characterized using X-ray diffraction, UV–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. According to X-ray diffraction results, no peaks related to silver or silver oxide were observed in the diffractograms of doped samples. Blue shift was observed in the absorption curve of Ag-doped Co3O4 nanoparticles compared to undoped Co3O4 nanoparticles. From transmission electron microscopy measurements, 2%, 4% and 6% Ag-doped Co3O4 nanoparticles thermal annealed at 500 °C exhibit sphere-like and irregularly structured morphology, while 10% Ag-doped Co3O4 nanoparticles have a rhombohedral-like, hexagonal and spherical morphology. The dielectric constant value (ɛʹ) was found to decrease with increasing frequency and it can be explained by Maxwell–Wagner model. The value of the dielectric constant increased with increasing of temperature from 25 to 100 °C and the highest value was observed for Ag0.1Co2.9O4/PVA sample at 100 °C temperature. [ABSTRACT FROM AUTHOR]

Gamma-irradiated samples of the polyethylene/CdS+ZnS (PE/CdS+ZnS) composite were studied by electron paramagnet resonance and Fourier infrared spectroscopy methods. Based on the electron paramagnet resonance spectra, the nature of the induced paramagnetic radiation defects and their quantitative dependence on the absorbed dose of gamma radiation are identified. It has been established that the studied polymer composites have a higher radiation resistance in the range of absorption doses D =30-100 kGy compared to pure polymer. The obtained results were confirmed by Fourier infrared spectroscopy, and it was shown that the observed changes are associated with a change in the supramolecular structure of PE/CdS+ZnS irradiated with-quanta. [ABSTRACT FROM AUTHOR]

Introducing of the methyl substituent into the C-C(H)=N moiety of the Schiff bases alters the tautomeric equilibrium in favor of the proton transfer forms in comparison with Schif bases deprived of such substituent and related Mannich bases is demonstrated. Accordingly, a scheme of proton transfer equilibria specific for Schiff bases is proposed, which is in agreement with numerous structural evidences.

The sequences of Fermi resonances νs ≈ 2νb in the IR spectrum of a fluoroform solution (CHF3) in liquefied krypton have been studied. Here, νs is the CH-stretching vibration and νb is the bending vibration. It has been shown that it is necessary to use an extended set of spectroscopic parameters for the correct description of resonant multiplets at a high degree of vibrational excitation. Among other factors, it is necessary to consider the dependence of the anharmonic interaction constant αsbb on the vibrational quantum numbers. The conclusions are generalized for the arbitrary case of the CH-chromophore CHX3. [ABSTRACT FROM AUTHOR]

The sequences of Fermi resonances νs ≈ 2νb in the IR spectrum of a fluoroform solution (CHF3) in liquefied krypton have been studied. Here, νs is the CH-stretching vibration and νb is the bending vibration. It has been shown that it is necessary to use an extended set of spectroscopic parameters for the correct description of resonant multiplets at a high degree of vibrational excitation. Among other factors, it is necessary to consider the dependence of the anharmonic interaction constant αsbb on the vibrational quantum numbers. The conclusions are generalized for the arbitrary case of the CH-chromophore CHX3. [ABSTRACT FROM AUTHOR]

Using Fourier transform IR spectroscopy, the radiation–thermal decomposition of water in the nano-ZrO2 + nano-SiO2 + H2O system in the temperature range of T = 373–673 K under the influence of γ-rays was studied. It is shown that water adsorption in zirconium and silicon nanooxides occurs by the molecular and dissociative mechanisms. Intermediate-active products of the radiation-heterogeneous decomposition of water—zirconium and silicon hydrides, hydroxyl groups—have been registered. The values of the velocities and radiation–chemical yields of molecular hydrogen during the radiolysis of water in the presence of nano-ZrO2 + nano-SiO2 mixtures were determined. It was revealed that the values of the velocities and radiation–chemical yields decrease on going from nano-ZrO2 to nano-SiO2. The stimulating role of radiation in the radiation–thermal decomposition of water in the temperature range of T = 373–673 K is shown. [ABSTRACT FROM AUTHOR]