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Electrochemical reduction in DMF is used to produce the radical anion of 2,4,6-trimethoxynitrobenzene with an EPR spectrum that shows hyperfine splitting for ¹⁵N nuclei of the nitro group and ¹³С nuclei of the benzene ring given the natural abundance of the isotopes. According to UB3LYP/6-31+G* quantum chemical calculations considering solvation in the PCM model, the nitro group in the equilibrium conformation of the RA of 2,4,6-trimethoxynitrobenzene is rotated relative to the benzene ring plane by an angle close to 90° and has a pyramidal structure. The calculated isotropic hyperfine coupling constants for this conformation are closest to the experimental results.

An internal-field ⁵⁹Co NMR study of cobalt-containing Fischer–Tropsch synthesis catalysts supported on different alumina modifications was reported. The Co/δ-Al₂O₃ sample was shown to contain single-domain fcc packing and stacking faults, whereas Co/γ-Al₂O₃ gave signals from the fcc domain walls, hcp and stacking faults, thus indicating differences in the particle size of the studied samples. T₂ relaxation times were measured; their distribution in a spectrum is non-uniform, which allows signals to be distinguished by their relaxation times. Quantitative measurements of the relative atoms content in different packings revealed that the catalysts have mostly a defect structure. A brief historical background was presented to characterize the internal-field ⁵⁹Co NMR technique, the related problems, and different approaches to acquired data interpretation.

A comparative analysis of ^6,7Li NMR spectra is performed for the samples of monoclinic lithium titanate obtained at different synthesis temperatures. In the ⁷Li NMR spectra three lines are found, which differ in quadrupole splitting frequencies ν_Q and according to ab initio EFG calculations are assigned to three crystallographic sites of lithium: Li1 (ν_Q ~ 27 kHz); Li2 (ν_Q ~ 59 kHz); Li3 (ν_Q ~ 6 kHz). The dynamics of lithium ions is studied in a wide temperature range from 300 K to 900 K. It is found that the narrowing of ⁷Li NMR spectra as a result of thermally activated diffusion of lithium ions in the low-temperature Li₂TiO₃ sample is observed at a higher temperature in comparison with a sample of high-temperature lithium titanate. Based on the analysis of ⁶Li NMR spectra it is assumed that there is mixed occupancy of lithium and titanium sites in the corresponding layers of the crystal structure of low-temperature lithium titanate, which hinders lithium ion transfer over regular crystallographic sites.

The structure of zeolite water in single crystals of natural zeolites represented by clinoptilolite Na₂K₂Ca[Al₆Si₃₀O₇₂]×22H₂O and heulandite Са₃Mg[Al₈Si₂₈O₇₂]×24H₂O is studied with ¹H NMR. Below 170 K the distribution of H₂O over the structural positions is shown to be fixed but different for the two minerals. Above 290 K translational and orientational diffusion of zeolite water molecules is observed and the structure of water is almost identical in both heulandite and clinoptilolite. Diffusion mechanism may be associated with the interaction between librational modes of H₂O and high-frequency oscillations of aluminosilicate framework. The microwave absorption is shown to be caused in certain conditions by this type of interaction.

⁵¹V NMR, DTA, and thermogravimetric analysis are used to study the thermal behavior of a manganese-nickel pyrovanadate complex Mn_2–2xNi_2xV₂O₇. It is shown that the nature of ⁵¹V hyperfine interactions in manganese pyrovanadate and solid solutions based on its polymorphic modifications is specified by the structurally activated oxygen exchange with the gaseous phase.

The ¹¹B NMR method is used to study the crystals of trigonal alumina borates Ho_1–xY_xAl ₃(BO₃)₄ (x = 0, 0.5, 1). The temperature-field evolution of quadrupole and hyperfine interactions in these compounds is studied and described.

Ionic mobility and phase transitions in heptafluorodiantimonates with homo- and heteroatomic cations in the systems MSb₂F₇ (M = K, Cs, NH₄) and CsM'Sb₂F₇ (M' = K, NH₄) have been studied using the ¹⁹F, ¹H NMR and DSC methods. Analysis of the ¹⁹F and ¹H NMR spectra made it possible to reveal the nature of ion motions in the fluoride and proton sublattices upon temperature variation and to determine the types and temperature ranges of such motions. It was found that diffusion of fluorine ions becomes the dominant form of ion motions in the high-temperature modifications, the amount of diffusing ammonium ions depending on the composition of a sample. The observed phase transitions in cesium–potassium and cesium–ammonium fluoroantimonates(III) leading to the formation of high-temperature modifications are the transitions to superionic state. According to preliminary results of electrophysical studies, high-temperature phases Cs_1–x(NH₄)_xSb₂F₇ (0.05 ≤ x ≤ 0.6) are superionic, their conductivity reaching ~10 ^–3—10 ^–4 S/cm at 463-483 K.

The dynamic structure of hydrogen sublattice in lawsonite, CaAl₂[Si₂O₇](OH)₂×H₂O is studied by the solid-state proton magnetic resonance (¹H NMR) spectroscopy of single crystal at room temperature. It is shown that both encapsulated water molecules, and hydroxyl OH-groups undergoes the rocking librations of the amplitudes of ~20° for H₂O, and ~40° for hydroxyls.

¹H, ²³Na and ²⁹Si solid-state NMR spectroscopy was used to investigate the formation of fiberglass zirconium-silicate supports and catalysts (glass → fiberglass → leached fiberglass → catalyst). The main emphasis was made on OH–H₂O domains in fiberglass and their role in catalyst preparation. The size of OH–H₂O domains and their accessibility to H–D exchange were determined. Platinum was shown to be anchored on the bridging hydroxyl groups. The quantum-chemical calculations demonstrated the activity of Pt⁰ clusters forming in fiberglass to depend on their nuclearity.

Ionic mobility of Li₄ZrF₈ (I) and Li_3.72Mg_0.14ZrF₈ (II) compounds has been studied over the temperature range of 300-420 K using ⁷Li, ¹⁹F broad-line NMR and NMR relaxation techniques. The fluorine sublattice in these compounds was found to be rigid, whereas in the lithium sublattice there occurs a diffusion with the activation energy of 0.2-0.3 eV. NMR data indicate the formation of lithium vacancies in solid solution II. MAS NMR of fluorine was used to determine the isotropic chemical shifts of its magnetically nonequivalent positions and to correlate these shifts with the crystal structure of Li₄ZrF₈.