Home – Home – Jornals – 2012 number 2

The Baidarik block of the Dzavhan microcontinent (Central Asian Fold Belt) includes the Upper Archean Baidaragin gray-gneiss complex. Among gray plagiogneisses, there are metabasic bodies, which are probably relics of early volcanics. By composition, the metabasites are divided into three petrochemical groups, whose protoliths were tholeiitic basalts, Al-undepleted and Al-depleted basaltic komatiites. Only a few samples are similar in REE composition to these protoliths. We have found metabasites with crustal-contamination features. The unusual geochemical properties of the metabasites (LREE enrichment and Nb, Zr, and Ti depletion) are related to their metasomatism.

New data are reported on the stratigraphy of the Oligocene deposits of Lake Baikal (the Tankhoi field, the outcrops near the mouths of the Osinovka, Polovinka, and Klyuevka Rivers). Detailed paleontological analysis of the key sections on the continental part of the Baikal eastern coast revealed four floristic horizons that could be used as indicator horizons and showed that the Tankhoi Formation formed throughout the Oligocene and at the early Early Miocene. Lithologically, blue vivianite clays and coal beds could be used as the most important indicator horizons. Formation of the deposits began after a long stratigraphic break from the Early Cretaceous to the Early Oligocene. The deposits were formed by erosion and denudation of weathering crust and accumulation of redeposited weathering residues in the Tankhoi paleobasin with a lacustrine-marsh landscape. Coarse-clastic foehn deposits of the Osinovka Formation, containing rich Miocene palynological assemblages, were eroded and overlie concordantly the Upper Tankhoi Subformation and redeposited weathering residues of the weathering crust, and underlie the Anosovka Formation. The study suggests that the Baikal rift valley began to form at 38 Ma.

The crustal orogeny which formed the present-day Tien Shan results from the complex interaction between two independent processes. The first is the lateral (horizontal) compression related to the collision between the Indian and Eurasian Plates. The second is the rearrangement and flow of crustal material at different levels of the lithosphere beneath the mountain belt. Two broad morphologic and genetic types of mountain basins (intramontane and intermontane/foreland) are proposed as indicators of specific geodynamic factors controlling the topographic relief of the orogenic belt. The first-type basins, having the upper crustal roots, reflect mainly the N-S crustal compression and correspond to simple (elementary) longitudinal folds with basement involvement. The second-type basins developed mostly in response to deep processes in the upper mantle and lower crust.

The recent geodynamics of the Far East region of Russia is considered, where three large tectonic plates converge - Eurasian, North American, and Pacific, as well as several microplates-Okhotsk, Bering, and Amurian - have been hypothesized to exist. The available data on the position of the plate boundaries, the relative plate rotation poles, and the regional seismicity were analyzed, and parameters of plate motion models for northeastern Russia were determined in this study. The regional deep structure was investigated, using data obtained by different geophysical methods. The results of observations of the Magadan-Vrangel Island profile by deep seismic sounding (DSS), common-depth point (CDP) method, and correlation refraction method (CRM) are presented.

The first tectonophysical model of the Baikal seismic zone represents a separate complex region of the lithosphere. It has a pinnate structure with a backbone belt of current deformation, which is a concentrator of largest earthquakes, and branching, repeatedly reactivated large and small faults. In its vertical section, the seismic zone is tree-like, the stem and the branches being faults of different size ranks which can generate earthquakes when reactivated. The real-time short-period fault motions and the respective seismicity occurring at a certain time and in certain places are triggered by strain waves, which disturb the metastable state of the faulted lithosphere subject to regional stress. The modeling work includes developing general requirements for tectonophysical models of continental rifts and special methods for identifying the faults that become active within short historic time spans, as well as techniques for locating potential events in space and time in specific active faults. The methods and model testing for medium-term earthquake prediction are described by the example of the well-documented Baikal seismic zone, which is the most active part of the Baikal rift system. The tectonophysical model for the Baikal zone is statistically supported by field data, and this allows estimating the velocities and periods of strain waves for different zone segments and faults, with implications for nearest-future earthquake prediction.

Effects of induced polarization (IP) often appear in TEM data collected in Yakutia and elsewhere in permafrost areas. Inversion of transient responses using the Cole-Cole model of frequency-dependent conductivity shows fast decaying induced polarization in the shallow subsurface (within 100 m). Frozen ground within these depths has the chargeability ( m ) in the range from 0.2 to 0.85 (mostly 0.2-0.5); the relaxation time constant (τ) varies from 35 to 250 ?s, being 50-100 ?s on average, and the exponent c is little variable, unlike m and τ (from 0.8 to 1). The latter fact ( c ≈ 1) is indicative of a narrow range of relaxation times fitting the Debye relaxation model. Conversion of the complex conductivity into relative low-frequency dielectric permittivity results in values of the order of tens of thousands or a few hundred thousand. These exceptionally high permittivities have no other plausible explanations than electrochemical polarization of unfrozen water that remains bound on the surface of mineral grains at subzero temperatures. The effects of electrochemical polarization are described and interpreted in terms of frequency-dependent surface conductivity, which is controlled by surface-to-volume ratio.

We consider different kinds of linear cloud anomalies appearing in satellite images over activated crustal faults. The spatiotemporal relationship between earthquakes and cloud anomalies was studied by statistical methods. It has been shown that these cloud anomalies in the atmosphere can be used for short-term prediction of the earthquake time and region. Also, we consider the earthquake-related evolution of the giant thunderstorm cloud near the epicenter before the earthquake.

Using ferromagnetic resonance and electron microscopy, dispersing bulk nickel and its alloys in the course of interaction with the reaction medium (1,2-dichloroethane and hydrogen) accompanied by the intense growth of carbon nanofibres was studied. It is demonstrated that in all the cases the formation of rather uniform nickel nanoparticles occurs with the characteristic size of 200–300 nm. The efficiency of this method for studying the formation of nickel particles at the very initial stages of the reaction was demonstrated, including the induction period, when the use of electron microscopic studies is not efficient enough.

Deep methanol oxidation in aqueous solutions with the methanol concentration lower than 2.0 mass % within temperature range 250–450 °С is considered. Experiments were carried out with industrial catalysts based on aluminum oxide with active components such as platinum as well as copper, chromium, iron, and magnesium oxides. The minimum concentration of methanol after oxidation (≤3 mg/dm³) was achieved for CuO/Cr₂O₃/Al₂O₃ catalyst. Most likely, the methanol oxidation on the catalysts of this type proceeds according to the Mars–van Krevelen mechanism, wherein reactive oxygen species responsible for deep oxidation are presented by the lattice oxygen of the catalyst. TPD spectra were obtained for oxygen, methanol, water, as well as for methanol and water in simultaneous presence, within the temperature range of 100–950 °С.

Composition, surface structure (including those after annealing at high temperature) and the catalytic activity in the steam conversion of naphthalene were studied for Ce-, Zr- and Mn-containing oxide layers obtained on titanium by means of plasma electrolytic oxidation. The composition and structure of oxide systems were studied by means of XRD phase analysis, energy dispersion analysis and scanning electron microscopy. It was demonstrated that Ce-, Zr-containing structures exhibit a rather high thermal stability: the elemental and phase composition, the structure of their surface remain almost unchanged after annealing in atmospheric air at the temperature values up to 800 °С. The catalytic studies demonstrated a rather high activity of Ce-, Zr-containing coatings in the reaction of naphthalene steam conversion at the temperature values up to 850 °С. Mn-containing oxide structures have developed surface covered with nanowhiskers those were not detected after thermal treatment. Mn-containing oxide systems exhibited a lower level of naphthalene conversion as compared to Се-, Zr-containing coatings, which could be connected with substantial changing their surface and with the formation of low-active fused manganese silicates at high temperature values.

Results are presented concerning the determination of lead and mercury total content in oligotrophic peat bog deposits in West Siberia. It is demonstrated that the current level of atmospheric lead fall-out is insignificant, the lead concentration in the upper layers of peat deposits are far below the level of background values established for other territories. Data concerning the mercury concentrations are comparable with those obtained earlier for other background areas. The distribution of elements depending on the physical and chemical properties of peat was revealed. A selective absorption of heavy metals by the humic and fulvic acids of peat organic matter was found to occur.

A series of environmentally safe highly efficient bifunctional catalysts for hexane skeleton isomerisation was studied. It was demonstrated that the activity of the catalysts is determined mainly by acidic properties. Reaction rate values and selectivity level with respect to target products were determined depending on the concentration of Lewis acid, whereas the content of Brцnsted acidic centers was maintained approximately constant. The data obtained could serve as a basis for the development of Russian highly efficient catalysts for light gasoline skeleton isomerisation those could be used for obtaining branched isomers for С₅-С₈ hydrocarbons with the octane number ranging within 92–105.

A method was developed for obtaining granulated sulphur-containing sorbents with the use of wastes from epichlorohydrin production containing about 76 % of 1,2,3-trichloropropane was developed. The interaction between the wastes and sodium polysulphide is carried out in the presence of petroleum coke particles playing the role of polycondensation centres. The sorbents obtained are capable of extracting metals from aqueous solutions to exhibit the following sorption capacity (mg/g): Zn up to 74, Cd up to 31, Hg up to 152, Cu up to 25. The sorption mechanism is under discussion.

A composition was studied for polycyclic aromatic hydrocarbons formed in the course of the pyrolysis (160–650 °С) of the resin-asphaltene components of heavy crude oil from the Permian–Carboniferous age deposits of the Usinskoye field (Komi Republic). It was demonstrated that the molecules of resins and asphaltenes inherent in the oil contain the same set of aromatic fragments. Among them there were identified bi- and tricyclic fused aromatic hydrocarbons and (С₁-С₃ alkyl derivatives, tetra -, penta -, hexacyclic substances and phenyl-substituted compounds (diphenyl-, phenylnaphthalenes, terphenyls, phenylphenanthrenes). Tri- and tetracyclic aromatic hydrocarbons are prevailing, which hydrocarbons should form the basis for the composition of oil fractions produced by means of thermal processing the heavy hydrocarbon feedstock.

Influencing the parameters of the crystallization process and the preparation of raw materials upon the quality of manganese acetate tetrahydrate was investigated. Optimum parameters were determined for the process of crystallization. Results are presented concerning studies on the influence of leaching the manganese carbonate upon the process purifying from calcium and chlorine impurities. A low-waste technological scheme is proposed for the production of high purity manganese acetate tetrahydrate.

Regularities were studied concerning dimethyl disulphide transformation in an atmosphere of helium in the presence of solid catalysts those differ from each other in the acid-base properties. The catalysts containing mainly BrØnsted acidic centres or strong basic centres on the surface exhibit a low activity level. Under the action of weak Lewis acidic centres, the dimethyl sulphide is formed at a low rate, however with increasing the strength of these centres the rate of dimethyl sulphide formation increases. For a catalyst to exhibit a high activity level in the formation of dimethyl sulphide, it is required for the presence of strong Lewis and BrØnsted centers, as well as basic centres with a moderate strength on the surface. The results of kinetic studies indicate that before 200 °C there is a parallel reaction scheme realized, whereas at a higher temperature the reaction scheme is consecutive. The reaction kinetic type varies from the first-order kinetics to zero-order one depending on the concentration of the substrate. The rate of dimethyl sulphide formation increases with increasing the temperature, the apparent activation energy amounts to (55±1) kJ/mol. The selectivity level of dimethyl sulphide formation in the case of complete conversion level of the substrate reaches 50–60 %.

Using the methods of XRD phase analysis, Raman and IR spectroscopy, thermogravimetry and chemical analysis the process of bismuth (III) citrate precipitation was investigated concerning the solutions of perchloric acid, nitric acid and hydrochloric acid under adding thereto a solution of citric acid or trisodium citrate. Conditions were determined with respect to the formation of compounds BiC₆H₅O₇, BiОC₆H₇O₇ · H₂O and Bi₆(OH)₆(C₆H₅O₇)₄ · 6H₂O. It was demonstrated that bismuth (III) citrate such as BiC₆H₅O₇ used in medicine for the synthesis of pharmaceuticals and in microbiology the production of bacterial preparations are appropriate to obtain via the precipitation from nitric acid solutions from manufacturing bismuth compounds with adding citric acid; the molar ratio between citrate ions and bismuth ions in the solution should be equal to 1.1–1.2, the process temperature being of (60±5) °С.

The bottom ash and fly ash investigated in this study originated from the bubbling fluidized bed boiler at the large-sized (246 MW) combustion plant of a pulp and paper mill complex. Approximately 40 % of the energy produced by the boiler originated from the incineration of commercial peat fuel, and approximately 60 % from the incineration of clean forest residues (i.e. bark, woodchip and sawdust). Due to the low heavy metal concentrations (As, Cd, Cr, Cu, Hg, Pb, Ni and Zn) in the bottom ash and fly ash, these residues are potential forest fertilizers as such. However, additional Ca is needed for the bottom ash, because its Ca concentration of 5.8 % (d.w.) was lower than the statutory Finnish minimum limit value of 6.0 % (d.w.) for Ca in forest fertilizers. Except for potassium, nutrients and heavy metals were enriched in the fly ash. Compared to the total phosphorous content, which was 0.2 % (d.w.) in the bottom ash and 1.3 % (d.w.) in the fly ash, the water soluble phosphorous content in both ashes was negligible (<0.01 %; d.w.). This finding is discussed on the basis of the minerals observed in the XRD data for the ashes, as well as on the grounds of findings reported by other researchers.

For the first time a pK spectroscopy technique was applied to study the influence of Lewis acids upon changing the acid-base properties of cellulose suspensions. Basing on the cellulose pK spectra obtained before and after the modification in the solution of titanium tetrachloride, it was demonstrated that the action of titanium tetrachloride on the cellulose results in weakening the bonds between hydrogen ions and appropriate acid-base groups, thereby the number of these groups remain unchanged. The powdered cellulose obtained under the influence of titanium tetrachloride differs from the original (fibrous) one in a high ion exchange capacity.

A series of sulphides belonging to pinane family was obtained basing on (1S)-(–)-β-pinene and its oxide. The asymmetric oxidation of β-hydroxysulphide with the fragment of 2-mercaptoethanol using an oxidizing system such as Ti(O-i-Pr)₄/R-C₆H₅CH(OH)COOH/t-BuOOH resulted in obtaining diastereomerically pure hydroxysulphoxide with pinane structure.

The stability of green tea catechins was studied in the solid phase and in aqueous solution in the course of storage, degradation rate values were determined depending on ambient conditions. The stability of catechins was investigated in the course of mechanical activation; possibility is demonstrated for obtaining a mechanocomposite consisting of plant raw material and ascorbic acid, with a higher stability.

Chelate complexes of selenium and iodine ions with the peptides of elastin protein were obtained. The parameters of sorption of selenium- and iodine-containing chelate complexes of elastin on natural zeolite tuff depending on the concentration of chelate complex and the time of contact between the chelate complex and tuff were studied.

By means of the ab initio DMol³ method Mo_nSi_m nanoparticles and fragments of Mo₃Si and MoSi₂ crystal lattices are theoretically modeled. For both crystals a few neutral Mo₄Si₆ and Mo₆Si₆ fragments of different shapes and symmetry are considered. In each case, after cluster separation its geometry is optimized, as a result of which the geometric structure noticeably changes and its stability increases. In order to theoretically search for the spatial configurations of Mo₄Si₆ and Mo₆Si₆ nanoparticle, two approaches are used: 1) in the most stable Fe₄C₆ and Fe₆C₆ isomers found previously, iron and carbon atoms are replaced by molybdenum and silicon respectively and then the geometry is optimized to obtain new equilibrium distances and angles; 2) the search for main Mo₄Si₆ and Mo₆Si₆ configurations is performed using the binominal scheme, starting from Mo₂, MoSi, and Si₂ dimers. The nanoparticle structures are found to contain metal atom chains and isolated pairs and triples of silicon atoms. In most cases, the nanoparticle stability proves to be higher than that of the crystal clusters.

Silicon nitride exhibits good mechanical properties and thermal stability at high temperatures. Since experiments have limitations in nanoscale characterization of the chemical structure and related properties, atomistic simulation is a proper way to investigate the mechanism of this unique feature. In this paper, the melt-quench method is used to generate the amorphous structure of silicon nitride; then the structural properties of silicon nitride under tensile deformation were studied by angular pair distribution functions. The corresponding mechanism of tensile stress induced structure rearrangement is explored.

The nature of metal-metal and metal-carbon bonding interactions within the penta- and tetra-ruthenium acetylide complexes [Ru₅(μ₄-C₂)L(CO)₁₃] (1) and [Ru₄(μ₄-C₂)L(CO)₁₀] (2) respectively are investigated using the present topological theories of the chemical bond: AIM and ELF. The electron density analysis within the framework of Atoms in Molecules (AIM) indicates that, in the first complex, only one bond path exists between the Ru4 and Ru5 metal atoms, whereas there is no direct bonding between ruthenium atoms in the second complex. On the other hand, the ELF analysis reveals that in both complexes, all Ru-C bonds belong to closed-shell type interactions and leads to the conclusion that the Ru-Ru bond is predominantly covalent. Moreover, the presence of trisynaptic basins in the first complex points out a three-center bond connecting ruthenium atoms.

Model Pb(II) thiocomplexes with mono- and bidentate ligands of the composition [Pb(L^1,2)_n]^2-n (L¹ is (SC₆H₅)^- (thiophenolate ion), L² is (S₂CN(CH₃)₂)^- (dithiocarbamate ion), n is the number of ligands of 2-6), which simulate fragments of the crystal structures of Pb(II) complex compounds with organic ligands, are studied within density functional theory. Geometric and energy parameters of model complexes with different coordination geometries of the Pb atom are determined and the stereochemical activity of the lone electron pair (LEP, E) of the Pb²⁺ ion is estimated in them. In the studied complexes, the highest Pb-S binding energy is found for the Pb atom surrounded by 2-4 ligands. The geometry of the Pb atom coordinated by S donor atoms can be described in terms of the valence shell electron pair repulsion (VSEPR) model with stereochemically active LEP. The coordination number (cn) of the Pb atom in the most energetically favorable complexes [Pb(SC₆H₅)_n]^2-n is (3+E) - (4+E), and in [Pb(S₂CN(CH₃)₂)_n]^2-n complexes, it is (4+E) and (6+E). Configurations with the mentioned cns are most often observed in the crystal structures of Pb(II) thiocomplex compounds.

According to the data of UB3LYP/6-31G* and UMP2/cc-pVTZ calculations, the adiabatic potential energy surface of the cyclopentane radical cation is very intricate and combines six types of stationary structures of C_s and C₂ symmetry. Ten equivalent C_s structures with the totally symmetric electronic state (C_s (²A′)) correspond to global minima. Conformational transitions between the global minima occur along the inversion and pseudorotation coordinates, for each pair of minima the conformational transition occurring in one stage (through the only transition state). The inversion barrier is ~2 kcal/mol; pseudorotation barriers are ~4-8 kcal/mol. The structure of the potential surface provides the interpretation of the EPR data as a result of dynamic averaging over 20 C_s (²A′) and C₂ (²A) stationary structures.

Ab initio quantum chemical methods are employed to study the spatial and electronic structure of a 1,4-dithiine molecule. Calculations are performed with electron correlation treatment by MP2 and B3LYP methods in 6-311++G(d,p) and 6-311G basis sets. It is found that the macrocyclization of 1,4-dithiine is energetically favorable. The addition of each subsequent dithiine ring decreases the relative energy of the system by ≈0.5÷2.3 kcal/mol. The cycle consisting of 7 dithiine rings is the most comfortable from the standpoint of the internal strain of the macrocycle. With an increase in the number of rings up to 10, the macrocycle starts to break into 4-, 5-, 6-, or 7-membered fragments. The formation of a nanotube based on a 7-membered macrocycle is energetically favorable. The inner diameter of this nanotube is 6.9 Å.

The molecular geometries and vibrational frequencies of the title compounds in the ground state are calculated using the Hartree-Fock (HF) and density functional theory (DFT/B3LYP) methods with the LANL2DZ basis set and compared with the experimental data. The calculated results show that the optimized geometries can well reproduce the crystal structural parameters, and the theoretical vibrational frequencies show good agreement with the experimental values. The energetic behavior of the title compounds in solvent media is examined using the B3LYP method with the LANL2DZ basis set by applying the Onsager and polarizable continuum model (PCM). In addition, molecular electrostatic potential (MEP) and frontier molecular orbital (FMO) analyses of the title compounds are investigated by theoretical calculations.

The local structure and the spin Hamiltonian parameters (the g factors g_i (i = x, y, z) and the hyperfine structure constants A_i) for Cu²⁺-doped Ca(OD)₂ are theoretically investigated from the perturbation formulas of these parameters for a 3d⁹ ion in an orthorhombically elongated octahedron. From the studies, the planar Cu²⁺-OD⁻ bonds are found to experience the relative variation ΔR (≈0.014 Å) along the X and Y axes, while those parallel to the Z axis may undergo the relative elongation ΔZ (≈0.25 Å) due to the Jahn-Teller effect. The theoretical spin Hamiltonian parameters based on the above local lattice distortions agree well with the experimental data. As compared with the previous treatments, the improvements of the theoretical spin Hamiltonian parameters are achieved in this work by adopting the uniform calculation formulas and the tetragonal field parameters based on the superposition model.

An artificial neural network (ANN) is constructed and trained for the prediction of gas to water partition coefficients of various organic compounds. The inputs of this neural network are theoretically derived from molecular descriptors that were chosen by the genetic algorithm-partial least squares (GA-PLS) feature selection technique. These descriptors are: area-weighted surface charge of hydrogen bonding donor atoms (HDCA-2), average bond order of a C atom (P_C), Kier flexibility index (Φ), atomic charge weighted partial positively charged surface area (PPSA-3), and difference between atomic charge weighted partial positive and negative surface areas (DPSA-3). By comparing the results obtained from PLS and ANN models, one can see that statistical parameters (Fisher ratio, correlation coefficient, and standard error) of the ANN model are better than those of the PLS model, which indicates that a nonlinear model can simulate more accurately the relationship between the structural descriptors and the partition coefficients of the investigated molecules.

Absolute intensities are calculated in the harmonic approximation for the IR spectrum of 18 hydrocarbons, oxygen- and nitrogen-containing organic compounds. The quantum chemical calculation is carried out in the 6-311G(3df,3pd) basis set. The calculated data are compared to the experimental values of absolute absorption intensities. It is found that calculations in the HF approximation substantially overestimate (on average by 87%) the integral absolute intensity of fundamental vibrations in the 575-4000 cm^-1 range. Most part of this overestimation falls on the stretching vibrations with large amplitudes (C-H and C=O bonds). When the MP2 method is used without electron correlation treatment, this overestimation decreases to 22% and becomes more uniform in the whole spectral region.

The structure of adducts forming in the solution due to the interaction of bifunctional azo compounds (dimethylpyrazole (DMP) and diphenylformamidine (DPFA)) with hydrogen halides (HF, HCl, and HBr) is found from the data of the IR absorption spectra and quantum chemical calculations. It is shown that in the interaction with HCl or HBr proton donors, proton transfer via the hydrogen bond to the basic N atom of the azo compound occurs with the formation of an NH⁺…Hal^- ionic pair. Strong evidences of proton transfer and the anion-cation pair formation are not found for the DMP-НF structure, and complexes with the molecular N…HF hydrogen bond are the dominant structures. Geometric parameters of the formed structures are calculated. The formation of trimers, containing two molecules of the azo compound and one HHal molecule, with an increase in the nitrogenous base concentration is experimentally proved, and the trimer structure is determined.

NMR and impedance spectroscopy are used to study the ionic mobility and conductivity in crystalline samples in PbSnF₄-MF systems (M = Li, Na, K) in a 150-473 K temperature range. The ¹⁹F NMR spectral parameters, types of ionic motion, and ionic conductivity value in the PbSnF₄ compound doped with alkali metal fluoride is found to be determined by the temperature, nature, and concentration of an alkali cation. The specific conductivity of the crystalline samples in PbSnF₄-MF systems (M = Li, Na, K) is rather high at room temperature and hence, it seems possible to apply them in the development of functional materials with high ionic (superionic) conductivity

The atomic structure of copper(II) complexes based on diacetyl monoxime 1′-phthalazinyl hydrazone is studied by XANES spectral analysis and magnetochemistry. The XANES spectra at the CuK-edge are measured in С₂₄H₂₄N₁₀Cu₂O₂ and С₂₄H₂₄N₁₀Cu₂O₂ complexes. The calculations of the CuK-XANES spectra of the complexes in question are performed for a few structural models based on the full-potential finite difference method. By low-temperature magnetochemistry magnetic exchange parameters are determined, and a quantum chemical simulation of the exchange interaction is carried out within the broken symmetry approximation. Based on a combined analysis of the XANES spectra and magnetic exchange parameters, the most probable structural models of С₂₄H₂₄N₁₀Cu₂O₂ and С₂₄H₂₄N₁₀Cu₂O₂ complexes are found.

By single crystal X-ray analysis, the atomic structure of the crystals of bis-phenanthrolinium hexachlorotellurate(IV) dihydrate (С₁₂Н₉N₂)₂TeBr₆·2H₂O (a = 7.4846(5) Å, b = 13.792(1) Å, c =
14.532(1) Å, β = 99.857(2)°, space group Р2₁/c, Z = 2, d_x = 2.259 g/cm³) is determined. The crystal structure is formed from separate anions [TeBr₆]^2-, cations of phenanthrolinium (С₁₂Н₉N₂)⁺, and water molecules. The electronic and geometrical aspects determining the spectral-luminescent and thermochromic properties of the complex are discussed.

The theory of the dependence of solvation numbers on the temperature is very popular today. However, according to our works, solvation numbers do not depend on temperature until the complete solvation limit is reached. The purpose of this paper is to address this apparent contradiction

The analysis of changes in the partial volume of glycine in solutions of substances that have a different effect on water structure is presented. For glycine in mixtures of water with glycerol and ethylene glycol, we derive a single equation for the dependence on the volume fraction of alcohol. The addition of tert-butyl alcohol, ethylene glycol, glycerol, and urea to water leads to a decrease in the hydration number of the amino acid (glycine dehydrates). In 1m solutions the losses of hydration water are 3.2%, 4.5%, 5.7%, and 7.6% respectively. In a 4m solution of tert-butyl alcohol, glycine loses 44% of hydration water, the same as in a 15m urea solution and a 20m glycerol solution. A contribution of the structural dehydration of glycine is observed in dilute aqueous solutions of t-BuOH. In more concentrated solutions, intermolecular interactions in the binary mixed solvent counteract dehydration. These interactions compensate for 15-22% of water lost by glycine in a 20m solution of urea, glycerol, and ethylene glycol and a 4m solution of t-BuOH. The partial volumes are also discussed within preferential solvation concepts.