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In this paper, an implicit method of decomposition of hermit cubic splines using the new type multiwavelets with supercompact supports is investigated. The splitting algorithm of wavelet-transformations on the parallel solution of two three-diagonal systems of the linear equations with strict diagonal domination is reasonable. The results of numerical experiments are presented.

A calculation scheme based on density functional theory with full geometry optimization, modified for structures with translational symmetry is applied to study the electron energy spectrum and magnetic characteristics of hexagonal gallium nitride and structures such as Y_xGa_{1– x}N (Y: donor (Ti) or acceptor (Zn) impurity). The dependence of relaxation shifts of interstitial atoms, the position of the chemical potential level, energy band boundaries, valence band widths, and energies corresponding to the intraband maxima of the density of states on the dopant concentration is discussed.

A quantum chemical and molecular dynamics simulation of a fragment of the sulfo cation exchanger in the form of glycine is performed. It is found that in the system studied an ionic pair dissociates.

The equilibrium geometries and vibrational frequencies of the ionic liquid 1-butyl-3-methylimidazolium cation and the alanine anion [BMIM][Ala] are studied using density functional theory (DFT) at the B3PW91/6-311+G(d,p) leve1. The most stable structures of the anion, the cation, and the ion pairs are obtained and characterized, and the geometry parameters of the ion pairs confirm the presence of a hydrogen bonding interaction between the anion and the cation. Natural bond orbital (NBO) analysis is also performed to analyze the atomic charge distribution and charge transfer in the [BMIM]⁺ cation and [BMIM][Ala] ionic liquids. The results show that there are the electrostatic interaction and multiple hydrogen bond interactions between the cation and the anion of the ionic liquids, and the stability of the ground state of the ion pairs mostly results from the hydrogen bonding between the lone pairs of O atoms in the anion and H in the imidazole cycle of the cation. There are some changes in microstructures and the charge distribution during the formation of the ion pairs.

A consistent calculation of frequencies and intensities of normal vibrations of some steroid phytohormones having biological activity (22S,23S)-24-epibrassinolide and (22S,23S)-28-homobrassinolide molecules) is performed within an original approach combining a classical normal mode vibration analysis by the molecular mechanics method and a quantum chemical estimation of absolute intensities. Based on a comparison of the experimental and theoretical spectral absorption curves the interpretation of IR spectral absorption bands is given for the first time and the effect of structural differences within the side chain of these molecules on the formation of their IR spectra in the range 1500-950 cm^–1 is estimated.

Potassium, rhubidium, and caesium fluorophosphatozirconates (hafnates) and oxo(hydroxo)fluorophosphatonitratometalates with PO₄^3-/Zr molar ratios of 2.0, 1.5, 1.0, 0.66, 0.5, and 0.33 are synthesized for the first time. Most of them form either fine crystalline or X-ray amorphous particles. In order to characterize them IR spectroscopy and SEM are used. For the crystalline compounds the types of PO₄ groups and the character of bonds between fluorine and water are revealed. The occurrence of triple МеF₄×Rb(PO₄)_0.33×RbNO₃ (Ме = Zr, Hf) salts and also M₃Me₃(PO₄)₅×3HF crystalline solvates is found. The layered habit of K₃Hf₃(PO₄)₅×3HF, RbHfF₂PO₄×0.5H₂O, Rb₃Hf₃(PO₄)₅×3HF, CsHfF₂PO₄×0.5H₂O, CsHf₂F₆PO₄×4H₂O, and CsH₂Hf₂F₂(PO₄)₃×2H₂O crystals gives grounds to suppose that the structure of these compounds is layered unlike the structure of triple МеF₄×Rb(PO₄)_0.33×RbNO₃ salts.

The heterobimetallic complexes [MMoO₂(L)(H₂O)₂] (where M = Zn²⁺ (1), Cu²⁺ (2), and Co²⁺ (4)) and [{MMoO₃(H₂L)(H₂O)₂}₂] (where M = Ni²⁺ (3) and Mn²⁺ (5)) are synthesized from bis(2-hydroxy-1-naphthaldehyde)malonoyldihydrazone (H₄L) using the monometallic precursor complex [MoO₂(H₂L)]×H₂O in ethanol. The composition of the complexes is established based on the data obtained from the elemental analysis and molecular weight determinations. The structure of the complexes is discussed in the light of data obtained from molar conductance, magnetic moment, electronic, EPR and IR spectroscopic studies.

A spectroscopic method for the analysis of compounds belonging to methanofullerenes with different functionalization and a number of substituents is developed. In order to determine the composition of mixtures of these compounds the standard spectrophotometric procedure along with derivative spectroscopy are applied. Acceptable reproducubility and sensitivity of the methods used are demonstrated on model mixtures of fullerene derivatives. The reaction mass obtained in the interaction of fullerene with diallyl ester of malonic acid is analyzed.

Data on the solubility of argon in water and aqueous solutions of L and D enantiomers of α-valine and α-phenylalanine at T = 283-328 K and partial pressure of argon p₂ = 0.1 MPa are used to calculate the standard parameters of the Sechenov salt effect. Parameters of the solute–solute pair interaction are estimated within the formalism of the McMillan–Mayer theory. Evidence is provided for the presence of the chiral effect in the Sechenov parameters.

Using the simulation method for the diffraction patterns of one-dimensionally disordered materials, the effect of different violations in the layered structure of aluminum trihydroxides (gibbsite and bayerite) on their diffraction patterns is analyzed. The features of the diffraction patterns of a disordered gibbsite sample obtained by intercalation–deintercalation of lithium salts are considered.