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Solid solutions of zinc sulfide with manganese and cobalt are synthesized. Based on the analysis of X-ray diffraction profiles the conclusion is drawn about the formation of a hexagonal wurtzite type structure in the synthesized quantum dot (QD) solutions. The average crystallite sizes are 8 nm and 22 nm for the samples with manganese and cobalt respectively. Results of IR and optical spectroscopy are consistent with the powder X-ray diffraction and X-ray fluorescence data. The question about particle aggregation in isopropanol and DMF solutions is considered. The QD structures based on ZnS particles doped with Mn and Co transition metal atoms are modeled. The possibility to apply X-ray absorption near edge structure (XANES) spectroscopy to verify the atomic structure parameters around the positions of doping transition metal atoms in QDs of the ZnS family is shown. Partial densities of ZnS:Mn and ZnS:Co electronic states are calculated.

The structural analysis methods are used to study the features of the local structure of nonstoichiometric strontium ferrites with a high concentration of oxygen vacancies depending on the degree of substitution by highly charged cations and external conditions. The ways of their structure adaptation for the compositions with oxygen stoichiometry beyond the homogeneity regions of vacancy-ordered phases are suggested: it occurs via the formation of modulated one- and three-dimensional disordered nanostructures.

The crystal structure of a natural sulfide Cu_3,44Ag_0,56Pb₂Bi₆S₁₃ ( Сmcm , Z = 4, a = 3.973(1) Å, b = 13.370(2) Å, c = 42.182(7) Å, R = 0.059) is determined. The structure has seven cation positions: two of them (Cu and Ag) are in a tetrahedral environment of sulfur atoms; one (Pb), in a special position (mm2), has a coordination polyhedron in the form of a bicapped trigonal prism; and the other cation positions are surrounded by sulfur atoms forming distorted octahedra. The mirror symmetry plane perpendicular to the c translation causes microtwinning by cutting a layer of trigonal prisms framed by tetrahedron ribbons. These layers are divided by those composed by edge-linked octahedra with a diagonal ribbon of five octahedra ( N = 5). The cation and anion positions are ordered by individual sublattices with pseudohexagonal subcells on the m planes perpendicular to the a translation, which concentrate the positions of all the atoms. Supposedly, this natural sulfide is the previously described (1885) yet unconfirmed alaskaite mineral from the lillianite-heyrovskyite homological series and may be isostructural to the ourayite mineral.

New double complex salts [RhL₄Cl₂][AuCl₄] (L = Py, γ- and β-picolines) are synthesized. The compounds are characterized by elemental, powder and single crystal X-ray diffraction analyses. The salts crystallize in different space groups. A specific feature of the packing of [AuCl₄]^- complex anions is the chain formation due to additional Au…Cl or Cl…Cl contacts.

The structures of two isostructural phases of [ M (Еn)₃](ReO₄)₂ ( M = Ni, Zn; Еn is ethylenediamine) are studied. The crystal structures belong to the triclinic system, but demonstrate a pseudohexagonal packing motif. It is shown that the product of thermal decomposition of [Zn(Еn)₃](ReO₄)₂ (hydrogen atmosphere, 400 °C) is a homogeneous mixture of nanocrystalline zinc and rhenium powders with coherent scattering regions of ~30 nm.

The crystal structures of isostructural mixed-ligand fluorosulfate complex compounds of indium(III) M₂[InF₃(SO₄)H₂O] (M = K, NH₄), formed of K⁺ cations, NH₄⁺ respectively, and complex [InF₃(SO₄)H₂O]^2- anions are determined. In the complex anion, the indium atom surrounded by three F atoms, the oxygen atom of the coordinated H₂O molecule, and two oxygen atoms of the bridging sulfate group forms a slightly distorted octahedron (CN 6). Via alternating bridging SO₄ groups, the polyhedra of In(III) atoms are arranged in polymer chains. The O-H⋯F hydrogen bonds organize the chains in a three-dimensional network. The K⁺ and NH₄⁺ cations are located in the structure framework and additionally strengthen it.

A new dimeric compound [{UO₂(μ-OH)(terpy)}₂](ClO₄)₂×0.67CH₃CN, containing an uranyl cation and a tridentate 2,2':6',2"-terpyridine (terpy) ligand, is synthesized from an acetonitrile solution of uranyl perchlorate and terpy. The crystal structure of the compound is determined by single crystal X-ray diffraction. The crystal structure shows the formation of symmetric and asymmetric cationic hydroxo-bridged uranyl dimers. The uranium atoms adopt a distorted pentagonal bipyramidal configuration with a UO₄N₃ coordination environment formed by two uranyl O atoms, three N atoms from the terpy ligand, and two O atoms from the hydroxide anions.

The X-ray diffraction study of new derivatives of perchlorate (9Н-xanthene-9-yl) and (4H-chromen-4-yl) triphenyl phosphonium is performed. It is demonstrated that the change in the molecular structure leading to a change in the degree of benzoannelation does not affect the phosphorus-carbon bond length. It is determined that perchlorate (2-phenyl-4Н-chromen-4-yl) triphenyl phosphonium сrystallizes as two polymorphs.

The crystal structure of the bimolecular crystal of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and methoxy- NNO -azoxymethane (МАМ) (1:2) is studied. The CL-20 molecules adopt a z-conformation. The crystal structure is formed by layers of CL-20 and МАМ molecules, between which there are shortened NO^d-⋯N^d+O contacts of the neighboring CL-20 and МАМ molecules.

A complex of physicochemical methods (powder XRD analysis, transmission and scanning electron microscopy, electron spectroscopy of diffuse reflectance, low-temperature nitrogen adsorption) is used for the comparative study of structural and morphological properties of oxide supports Ce_{1- x} M _x O _y (M = Gd, La, Mg; x = 0-0.5; 1.5 ≤ y ≤ 2.0) for catalysts for the autothermal reforming of bioethanol to a hydrogen-bearing gas. It is shown that Ce_1-x M _x O _y samples synthesized by the method of ester polymer precursors are mesoporous materials being the homogenous substitutional solid solutions with the fluorite-type cubic structure. The structural and textural properties of the Ce_1-x M _x O _y materials are regulated by varying the type of the dopant cation (M = Gd, La, Mg), the molar ratio M/Ce (0, 0.1, 0.25, 1), and heat treatment conditions (temperature 300-800 °C; duration 4-24 h). The relationship between the synthesis parameters and the characteristics of the Ce_1-x M _x O _y materials is found.