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(NH₄)Sb₄F₁₃ crystals (I) are synthesized and their crystal structure (tetragonal crystal system: a = 9.6431(2) Å, c = 6.5503(2) Å, V = 609.11(3) ų, Z = 2, d_calc = 4.100 g/cm³, F (000) = 664, space group I ) is determined. The main structural units of I are tetranuclear anionic [Sb₄F₁₃]^- complexes and [NH₄]⁺ cations. The anionic complexes are built of four SbF₃ groups linked together by tetrahedral bridging fluorine atom. At room temperature the (NH₄)Sb₄F₁₃ crystals are isostructural to previously studied МSb₄F₁₃ (М = K, Rb, Cs, and Tl). The study of ^121,123Sb NQR spectra of compound I is performed in a range of 77-370 K, which shows that when the temperature decreases (<250 K) the substance exhibits piezoelectric properties, as do other compounds of this group, but with a violation of their isostructurality.

The g factors for Cu²⁺ in meta-zeunerite (Cu(UO₂)₂(AsO₄)₂×3H₂O), kroehnkite (Na₂Cu(SO₄)₂x2H₂O), copper benzoate (Cu(PhCO₂)₂×3H₂O) and diaboleite (Pb₂Cu(OH)₄Cl₂) of the tetragonal phase are uniformly treated by high order perturbation formulas for 3d⁹ ions in tetragonally elongated octahedra. The calculation results are in good agreement with the observed values and systematically analyzed in view of the local structures around Cu²⁺. The g anisotropies Δg (= g_|| - g_|) are largely ascribed to the local tetragonal elongations of the Cu²⁺ sites, characterized by the relative elongation ratios ( R_|| - R_|)/ ≈ 19 %, 21 %, 27 % and 30 % for meta-zeunertie, kroehnkite, copper benzoate and diaboletie, respectively. The anomalous valley (minimum) of relative g anisotropy for copper benzoate is attributed to the modification of the Cu²⁺ electronic states due to the phenyl ring. The ligand orbital contributions are found to be significant due to covalency, and should be taken into account. The present study would be helpful to the unified investigations of structures and properties of the copper oxygen compounds.

The work proposes a method to predict changes in the heat capacity of the liquid-vapor phase transition (298.2) based on modified Randič indices for alkanes and acyclic oxygen-containing compounds: alcohols, aldehydes, ketones, ethers, and esters. Based on the obtained (298.2) values heat capacities in the liquid phase (298.2) are calculated for the compounds under study.

The work analyzes both literature data on the dependence of the internal liquid pressure on thermodynamic parameters of state and theoretical ideas of the nature of the internal pressure. The analysis enables the formulation of a hypothesis: the temperature coefficient of the internal liquid pressure corresponds to the state of its force field and the dynamics of this coefficient follows the course of changes in the macroscopic force field of liquids. The hypothesis underlies the construction of a scale of states of the own force field of liquids. To substantiate this scale, and consequently, the formulated hypothesis, the scale is verified with respect to water. A unified scale of states of force fields of associated liquids is proposed.

By a reaction of [BiX₆]^3- with salts of various N-alkylated pyridine derivatives in 2M HX (X = Cl, Br), (N-BzPy)₄[Bi₂X₁₀] complexes (X = Cl (1), Br (2), (4-MePyH)₄[Bi₂Cl₁₀] (3)) are obtained and structurally characterized.

Crystals of bis(4-aminopyridinium) dichromate (C₅H₇N₂)₂[Cr₂O₇] (1) were isolated via slow solvent evaporation and characterized by energy dispersive spectroscopy (EDS), infrared (IR) and ultratviolet-visible (UV-Vis) spectroscopy, and single crystal X-ray diffraction. The room-temperature (RT; 298 K) phase of 1 crystallizes in the monoclinic space group P2₁/m. Its asymmetric unit consists of two crystallographically independent 4-aminopyridinium cations (A and B) and two halves of symmetry-independent dichromate anions (A and B). Cations and anions are linked with the aid of several moderate N-H⋯O hydrogen bonds and weak C-H⋯O interactions resulting in a three-dimensional supramolecular network. The crystal structure is further stabilized by extensive p-p stacking interactions between adjacent pyridine rings. A comparison of the structure of the RT phase of 1 and that of the low temperature (LT; 150 K) phase is described.

A new complex [Cu(L¹)(NCS)]SCN, where L¹ = 3,14-dimethyl-2,6,13,17-tetraazatricyclo(16.4.0.0^7,12)docosane is prepared and characterized by single crystal X-ray crystallographic analysis. The complex crystallizes in the triclinic space group P with two mononuclear formula units in a cell of dimensions a = 7.9681(2), b = 8.8644(2), c = 18.8165(5) Å, α = 76.758(70), β = 78.490(2) and γ = 77.679(2)°. The Cu(II) ion is five-coordinate in an axially elongated square pyramidal environment, with the four amine N atoms at the equatorial positions and the N atom of one thiocyanate at an apical site. The macrocyclic cyclam moiety adopts a stable trans-III configuration. The Cu-N basal plane bond length has a mean value of 2.037(2) Å. The coordinated Cu-NCS bond length is 2.322(3) Å. The N atom of the thiocyanate anion is connected to the macrocyclic ligand of the cation via an NH…N(CS) hydrogen bond. The UV-visible absorption and IR spectral properties are also discussed.

Two new cadmium(II) coordination polymers, {[Cd(L1)(tbta)]×H₂O}_n (1) and [Cd(L2)(tbta)]_n (2) (L1 = 1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, H₂tbta = tetrabromoterephthalic acid and L2 = 1,4-bis(2-methylbenzimidazol-1-ylmethyl)benzene) are obtained under hydrothermal conditions and structurally characterized by single crystal X-ray diffraction methods, IR spectroscopy, TGA and elemental analysis. The L1 and L2 ligands differ by subtle variation of substituents at semi-rigid bis(benzimidazole) bakcbones. Complex 1 features a 3D threefold interpenetrating dia array with a 4-connected 6⁶ topology. Complex 2 displays a 2D {4⁴.6²} sql/Shubnikov tetragonal plane network. Complexes 1 and 2 possess high thermal stabilities and promising fluorescence behavior in the solid state.

A new Mo₂O₃(dpm)₄ compound (I) is synthesized by the interaction of Mo(CO)₆ with 2,2,6,6-tetramethylheptanedione-3,5 (dpm). The structure of complex I determined by the XRD method is as follows: triclinic crystal system, space group P-1, a = 10.1780(7) Å, b = 10.1817(6) Å, c = 13.3255(9) Å, α = 110.562(2)°, β = 102.233(2)°, γ = 93.9041(19)°, V = 1248.17(14) ų. The compound is characterized by IR spectroscopy, mass-spectrometry and thermogravimetric analysis (TGA).

The crystal structure of 1,1-bis(methoxy-NNO-azoxy)-3,3,3-trinitropropane is studied.