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The structural and thermodynamic characteristics of aqueous solutions of formamide, N-methylformamide, N,N-dimethylformamide, and N,N-diethylformamide were calculated. The specific and nonspecific components of the total energy of intermolecular interactions were determined. The limits of the concentration regions with differently arranged structures of solutions were established, and the preferable solvation parameters of the solution components were evaluated.

The dependence of the binding energies in molecules and crystals on the interatomic distances near the equilibrium position was established in the framework of the Mie equation using the force constants of molecules and the elasticity moduli of solids. To evaluate the repulsion forces, we used the Morse function for molecules and the Born-Landé approach for ionic crystals.

The crystals of a heterobimetallic complex based on lead(II) hexafluoroacetyl acetonate and copper(II) trifluoroacetyl acetonate were investigated by X-ray diffraction. Crystal data for Cu(tfa)₂⋅Pb(hfa)₂: a = 9.3991(4) Å, b = 11.7816(5) Å, c = 13.9736(5) Å, α = 88.311(2)°, β = 89.972(1)°, γ = 76.326(1)°, space group P-1, Z = 2, d_calc = 2.190 g/cm³. The basic structural motif for the complexes is coordination polymer in the form of chains of alternating complex molecules. The Cu(tfa)₂ molecules have a trans configuration. The results of a DTA-TG analysis of the compound are given.

New volatile β-iminoketonate complexes of Ni(L)₂ and Pd(L)₂ were obtained. β-Aminovinylketone C(CH₃)₃C(NH₂)CHC(O)C(CH₃)₃ was used as HL. Synthesis of the compound is described, and element analysis, DTA, and IR spectral data are given. The complexes were investigated by XRPA and XRD. The structures are molecular, consist of the trans complexes, and are isostructural. The central atoms have a square plane environment with a (MO₂N₂) coordination unit. The M-О and M-N distances and the N-M-O valence chelate angles are equal, 1.834 Å, 1.848 Å, and 94.2° for Ni(L)₂ and 1.972 Å, 1.975 Å, and 92.4° for Pd(L)₂.

The crystal structures of the Rh[(EtO)₂PS₂]₃ (I) and Co[(PhO)₂PS₂]₃ (II) chelate compounds were determined from X-ray diffraction (XRD) data (CAD-4 diffractometer, MoK_α radiation, 1193 F_hkl, R = 0.0516 for I and 513 F_hkl, R = 0.0305 for II). Crystals I are monoclinic: a = 14.233(3) Å, b =13.570(3) Å, c = 14.272(3) Å; β = 90.66(3)°, V = 2756.3(10) ų, Z = 4, ρ_calc = 1.587 g/cm³, space group C2/c. Crystals II are trigonal: a = 15.149(2) Å, c = 30.306(6) Å; V = 6023.2(16) ų, Z = 6, ρ_calc = 1.493 g/cm³, space groupR3. Structures I and II consist of discrete mononuclear molecules. The coordination polyhedra of the M atoms (M = Rh, Co) are distorted octahedra formed by six sulfur atoms of three cyclic bidentate ligands.

The molecular and crystal structure of dimethyl-(1,4-dimethyl-7-ethylazulyl)-sulfonium perchlorate and dimethyl-(1,4-dimethyl-7-isopropylazulyl)-sulfonium perchlorate was determined by X-ray diffraction analysis. Their crystal structure is mainly determined by C-H…π intermolecular interactions.

The hydroquinone-dimethyl sulfoxide-toluene system was investigated by thermal and X-ray diffraction analyses. The crystal structure of the 1:1 complex of hydroquinone with dimethyl sulfoxide was determined. Crystal data: C₈H₁₂O₃S, M = 188.24, triclinic system, space group P1, unit cell parameters: a = 7.4202(2) Å, b = 8.4046(3) Å, c = 8.7340(3) Å; α = 100.830(1)°, β = 99.794(1)°, γ = 114.129(1)°; V = 469.35(4) ų, Z = 2, d_calc = 1.332 g/cm³, R1 = 0.028, T = 100 K. The molecules are linked in a supramolecular assembly via D-H…A hydrogen bonds (D = O, C; A = O, π).

Synthesis, X-ray phase analysis (XRPA), and IR spectroscopic study were performed to investigate the structure of [Cu(m-HBH)₂(OH₂)₂]SO₄⋅H₂O, where m-HВН = С₇Н₈О₂N₂ (3-hydroxybenzoylhydrazine); а = 7.154(3) Å, b = 8.012(2) Å, c = 20.061(2) Å, β = 90.56(2)°; P2₁, Z = 2, R(F) = 0.046. The structure of the compound consists of the [Cu(m-HBH)₂(OH₂)₂]²⁺ complex cations, anions, and one water molecule. The copper atom is surrounded by a tetragonal bipyramid; c.n. is 6 = 4 + 2 (the distances are 2.030(5) Å, 2.054(6) Å, 2.061(5) Å, and 2.097(3) Å (equatorial); 2.459(4) Å and 2.53(4) Å (axial)). In complex compounds of 3d metals containing m-HВН, the function of the latter is probably invariable; the distribution of the anions and water molecules in the structure depends on the type of the metal and on the anion shape and geometry for metals with slightly different ionic radii.

A Cu₁O_1.7 oxide film containing a large amout of superstoichiometric oxygen was obtained by low-temperature oxidation of metallic copper in the oxygen plasma. An STM study of the film structure showed that ~10 nm planar copper oxide nanocrystallites with particles packed parallel to the starting metal surface. In an XPS study, the spectral characteristics of the Cu2p and O1s lines indicated that particles with a CuO lattice formed (E_bnd(Cu2p_3/2) = 933.3 eV and a shake-up satellite, E_bnd(O1s) = 529.3 eV). The additional superstoichiometric oxygen is localized at the sites of contact of nanoparticles in the interunit space and is characterized by a state with the binding energy E_bnd(O1s) = 531.2 eV. Due to the formation of a nanostructure in the films during low-temperature plasma oxidation, the resulting copper oxide has a much lower thermal stability than crystalline oxide CuO.

The current state of research on the nature of the chemical bond and the physicochemical properties of binary Th-X (X = H, B, C, N, O, P, S, As, Se, Sb) and ternary (carbonitrides, thorates, and silicates) thorium compounds by modern ab initio methods of the band structure theory is reviewed. The possibilities of the ab initio band structure methods in describing the structural states, phase stability, elasticity characteristics, X-ray emission, absorption, and photoelectron spectra of thorium-containing systems are discussed.