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The phonon spectra of a series of А²В⁴С⁵₂ and А¹В³С⁶₂ crystals with the chalcopyrite structure are calculated in the Keating model in the basis set of polarization vectors of their sublattices. The dependences of frequency values and partial contributions of sublattices to the polarization vectors on the chemical composition are studied. The effect of the mass ratio and the strengths of covalent bonds between the compound components on the phonon spectrum formation is found.

The adsorption of CO and C₂H₂ molecules on the perfect basal surface of graphite is investigated by adopting cluster models in conjunction with quantum chemical calculations. The noncovalent interaction potential energy curves for three different orientations of CO and C₂H₂ molecules with respect to the inert basal plane of graphite are calculated via semi-empirical and Möller-Plesset ab initio methods. Then, we have considered the effects of interaction energies on the C≡O and C≡C bond lengths by performing the partial geometry optimization procedure on the CO-graphite and C₂H₂-graphite systems in various intermolecular distances. The computational analysis of all physical noncovalent potential energy curves reveals that the relative configurations in which CO and C₂H₂ molecules approach the graphite sheet from out of the plane have stronger interaction energy and so is more favorable from the energetic viewpoint. This means that the graphite layer prefers to increase its thickness via the chemical vapor deposition of CO and C₂H₂ on the graphite.

Within DFT (B3LYP) methods the potential surface of the interaction between 1-iodopropan-2-one and 1,2,3-benzotriazole resulting in the formation of 1,3-bis(2-oxopropyl)-3Н-1,2,3-benzotriazolium triiodide is studied. A mechanism consisting of four steps (N-1-alkylation of 1,2,3-benzotriazole, elimination of molecular iodine during partial reduction of 1-iodopropan-2-one with hydrogen iodide, formation of the triiodide structure, and formation of 1,3-bis(2-oxopropyl)-3Н-1,2,3-benzotriazolium) is proposed. Thermodynamic and kinetic parameters of these steps are obtained.

The molecular structure of chromium and cobalt tris-acetylacetonates is studied by the synchronous electron diffraction and mass spectrometric experiment and quantum chemically. It is found that molecules have the D₃ symmetry with internuclear distances r_h1(Cr–O) = 1.960(4) Å and r_h1(Co–O) = 1.893(4) Å. Quantum chemical calculations by the DFT methods with different basis sets yield a structure well consistent with that found in the experiment. Changes in the structural parameters of chromium and cobalt b-diketonate complexes whose ligands differ in –CH₃, –C(CH₃)₃, –CF₃ substituents are considered.

The ferromagnetic resonance (FMR) method in situ is used to study the initial stages of the formation of ε iron oxide nanoparticles deposited on silica gel at temperatures up to 600°C. It is shown that at high-temperature treatment of starting samples obtained by impregnation with an iron(II) sulfate solution, supermagnetic ε-Fe₂O₃/SiO₂ nanoparticles form with a narrow size distribution. An analysis of the FMR data in comparison with the data of other methods enables the formulation of the formation conditions for systems of deposited ε-Fe₂O₃ nanoparticles without other polymorph impurities.

Single crystal XRD is used to determine the structures of the complexes (H₂TMEDA)[Mg(ptac)₃]₂ (1, TMEDA = Me₂N(CH₂)₂NMe₂, ptac = ^tBuCOCHCOCF₃) and (H₂TMEDA)[Mg(hfac)₃](hfac) (2, hfac = CF₃COCHCOCF₃) at a temperature of 150 K. The crystallographic data for complex 1: a = 10.2919(3) Å, b = 10.9492(4) Å, c = 15.4159(6) Å, α = 87.117(1)°, β = 89.686(1)°, γ = 79,864(1)°, space group Z = 1, R = 0.0573; for complex 2: a = 12.9446(2) Å, b = 23.0035(4) Å, c = 13.1473(3) Å, α = 90°, β = 98.779(1)°, γ = 90°, space group P2₁/n, Z = 4, R = 0.0605. The structures are ionic; the metal atom coordinates six oxygen atoms of three β-diketonate ligands. The distances Mg–O in complex 1 are in the range 2.036(2)-2.0920(19) Å; the same distances in complex 2 are in the range 2.051(2)-2.076(2) Å. The spatial packing is determined by the system of hydrogen bonds between the (H₂TMEDA)²⁺ cations and [Mg(ptac)₃]^– (1) or hfac^– (2) anions. A thermogravimetric study of complex 1 is carried out.

The structure of supports (ceria and zirconia) for supported copper catalysts for the processes of hydrogen obtaining and purification is studied. The formation features of the structure of zirconia annealed at 300-1000°C are identified at different levels: the atomic one and the level of the structural arrangement of secondary particles when the formation of agglomerated block structures with large number of grain interfaces occurs. The formation process of copper oxides on different supports is studied.

N1s and O1s X-ray photoelectron spectra of stable nitroxyl radicals (substituted piperidine-1-oxyl, 2-imidazoline-1-oxyl, and 2-imidazoline-3-oxide-1-oxyl) and also diamagnetic derivatives with a {ONCNO} fragment are measured. It is shown that the structure of N1s and O1s X-ray photoelectron spectra of nitroxyls is determined by charge transfer processes between different parts of the molecule to screen the X-ray hole and the spin-spin interaction of unpaired electrons on the HOMO and 1s level.

In the samples of the Na₂MoO₄–MgMoO₄ system quenched in the air at above 600°C, by powder X‑ray diffraction two double molybdates of variable composition are detected: monoclinic alluaudite-like Na_4–2xMg_1+x(MoO₄)₃ (0.05 ≤ x ≤ 0.35) and triclinic Na_{2–2 y}Mg_2+y(MoO₄)₃ (0.10 ≤ y ≤ 0.40) isostructural to previously studied Na₂Mg₅(MoO₄)₆. Sodium-magnesium molybdate of the Li₃Fe(MoO₄)₃ structure type is not revealed in this system. By spontaneous flux crystallization, the crystals are obtained and the structures of two triclinic double molybdates of the Na₂Mg₅(MoO₄)₆ structure type (space group P1, Z = 1) containing magnesium and manganese are determined. The results of the refinement of site occupancies made it possible to determine the composition of the studied crystals: for the compound with magnesium (Na)_0.5(Na_0.25⟩_0.75)(Na_0.75Mg _0.25)Mg₂(MoO₄)₃ or Na_1.50Mg_2.25(MoO₄)₃ (a = 6.9577(1) Å, b = 8.6330(2) Å, c = 10.2571(2) Å, α = 106.933(1)°, β = 104.864(1)°, γ = 103.453(1)°, R = 0.0188); for the compound with manganese (Na)_0.5(Na_0.32⟩_0.68)(Na_0.82Mn_0.18)Mn₂(MoO₄)₃ or Na _1.64Mn_2.18(MoO₄)₃ (a = 7.0778(2) Å, b = 8.8115(2) Å, c = 10.4256(2) Å, α = 106.521(1)°, β = 105.639(3)°, γ = 103.233(1)°, R = 0.0175). The Na₂Mg₅(MoO₄)₆ structure is redetermined and it is shown that actually it corresponds to the composition Na_1.40Mg_2.30(MoO₄)₃.

A new azido-coordinated nickel(II) complex [NiL¹(N₃)] (1) and a new thiocyanato-coordinated nickel(II) complex [NiL²(NCS)] (2), where L¹ and L² are the monoanionic forms of Schiff bases 2-[(2-isopropylaminoethylimino)methyl]-6-methylphenol and 2-[(2-dimethlaminoethylimino)methyl]-6-methylphenol respectively, are prepared and structurally characterized by elemental analysis, IR spectra, and single crystal X-ray crystallography. Complex 1 crystallizes in the triclinic space group P-1 with unit cell dimensions a = 8.812(2) Å, b = 9.433(3) Å, c = 9.488(2) Å, α = 81.933(2)°, β = 69.925(2)°, γ = 84.591(2)°, V = 732.5(3) ų, Z = 2, R₁ = 0.0291, and wR₂ = 0.0734. Complex 2 crystallizes in the monoclinic space group P2₁/n with unit cell dimensions a = 7.4497(4) Å, b = 6.1933(3) Å, c = 31.5126(18) Å, β = 92.484(2)°, V = 1452.57(13) ų, Z = 4, R₁ = 0.0307, and wR₂ = 0.0668. The Ni atom in each of the complexes is coordinated by three donor atoms of the Schiff base ligand and by one N atom of the azide or thiocyanate ligand, forming a square planar geometry. The azide and thiocyanate anions readily coordinate to the complexes as secondary ligands.