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It is shown that a model system of random walk of particles with superimposed vortex motion simulates the specific behaviors of a two-particle correlation function DP ( t ) = <[r _i ( t ) - r _i (0)]×[r _k ( t ) - r _k (0)]>, which are observed in molecular dynamics models of water and liquid argon. Hence, in liquids there well may be mesoscopic-sized vortices (of the order of ten intermolecular distances).

Crystallographic analysis of the known structure of TlHg₆S₄Br₅ reveals that the Tl⁺ cation occupies the S^2- site, centering the cubic Br subcells in the unit cell. The analysis shows that Tl is located in one sublattice with Br and S anions, and the Hg cationic sublattice, which has a relatively small size and large amount of vacant sites, is coordinated with the anionic one due to the selective site occupation in the former. An algorithm is considered for calculating the compositions with a given proportion of large monovalent cations substituting for S.

Vanadium complexes have been proved to possess an interesting insulin-like activity. The reaction of VO(acac)₂ with N ¢-(3,5-dichloro-2-hydroxybenzylidene)-2-methylbenzohydrazide (H₂L) in methanol affords a new mononuclear vanadium (V) complex [VOL(OMe)(MeOH)]. The structure of the complex is characterized by physicochemical methods and single crystal X-ray diffraction. The complex crystallizes as the monoclinic space group P 2₁/ n , with unit cell parameters a = 7.830(2) Å, b = 23.225(3) Å, c = 10.635(2) Å, b = 101.947(2)°, V == 1892.1(6) ų, Z = 4, R ₁ = 0.0404, wR ₂ = 0.0953, S = 1.037. The X-ray analysis indicates that the V atom in the complex is in the octahedral coordination. The insulin-like activity of the complex is studied.

The title complex is synthesized and analyzed using single crystal X-ray diffraction studies. The asymmetric unit [RuCl₃(CO)(PPh₃)₂] of the title complex contains one half of the molecule. The molecular structure is stabilized by C3-H3…Cl1 and C9-H9…Cl2 intramolecular halogen interactions which result in two S(6) ring motifs. The crystal packing features are the C-H…Cg1 interactions, where Cg1 is the center of gravity of the phenyl ring (C14-C19). No classical hydrogen bond is found in the complex.

The interaction of the quaternary thioselenobromide complex Os₂S₇Se₅Br₈ prepared by the reaction of OsO₄ with a solution of sulfur in Sе₂Br₂ at 100°C with melted 4-CNPy at 165°C leads to the formation of the Os₂S₂Br₄(4-CNPy)₄ complex whose structure is determined by single crystal X-ray diffraction.

A new compound C₆F₅N(H)C(O)CH₃ pentafluoroacetanilide, which is promising for the formation of coordination compounds with metal cations, is synthesized. Its crystal structure is determined (APEX DUO diffractometer, lMo K _a, graphite monochromator, T = 150 K). Crystallographic data for C₈H₄F₅NO are as follows: space group C 2/ c , a = 18.2460(7) Å, b = 10.5840(4) Å, c = 9.4489(4) Å, b = 116.198(1)°, V = 1637.28(11) ų, Z = 8. The compound has a molecular structure formed of isolated pentafluoroacetanilide molecules. The average distances in the phenyl ring are 1.39 Å for C-C and 1.34 Å for C-F. The molecular structure of the studied compound is confirmed by ¹⁹F and ¹H NMR in the solution CCl₄/CDCl₃ = 1:1 (v:v).

The crystal structure and structural features of the 7-phenyl-9,11-dihydrochromeno(4,3-b)pyrazolo(4,3-e)pyridine-6(7 H )-one molecule obtained according to the Biginelli reaction in the interaction of 4-hydroxy-2 H -chromen-2-one, benzaldehyde, and 1 H -pyrazole-5-amine are determined by single crystal X-ray diffraction.

The reaction of diethyl-5-methyl-3-oxo-1,2,3,6-tetrahydro-[1,1¢-diphenyl]-2,6-dicarboxylate with (1-(4-bromophenyl)ethylidene)hydrazine is conducted, and the crystal structure of the product of this reaction (diethyl-5-(2-(1-(4-bromophenyl)ethylidene)hydrazinyl)-3-methyl-1,2-dihydro-[1,1¢-diphenyl]-2,6-dicarboxylate) is determined by single crystal X-ray diffraction. The conformation of the cyclohexadiene ring in the form of a strongly distorted half-chair is determined based on the X-ray diffraction data. The presence of the intramolecular hydrogen bond of the N-Н…О=C type is noted.

To the best of our knowledge, it is the first time that the method of chemical vapor deposition (MOCVD) with platinum(II) bis(acetylacetonate) (Pt(acac)₂) is used to obtain platinum coatings on the cathodes and anodes of the electrodes for pacemakers. The deposition processes are carried out under reduced pressure in the presence of oxygen. The phase and elemental composition, structure, and morphology of the coatings are examined by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Platinum coatings with a columnar structure are prepared in the temperature range 280-340°C. An increase in the deposition temperature leads to a change in the structure of the coatings and reduction in their thickness. Cyclic voltammetry (CV) is used to estimate the specific capacities of the platinum coatings on the cathodes and anodes, the maximum values of which are 426 mC/cm² and 1160 mC/cm², respectively.

It is found that electron delocalization indices can be efficiently used as a sorting tool for the classification of bonds between iodine atoms in a wide range of various covalent and noncovalent I…I/I-I interactions. The characteristics of bonds in a symmetrical triiodide anion can serve as benchmarks allowing to distinguish the I…I halogen bond from the I-I covalent bond.