Two new polymeric networks, [Co(pbbm)(nip)] · H₂O (1) and [Ni(pbbm)(nip) · (H₂O)] (2) (pbbm = 1,1-(1,3-propanediyl)bis-1H-benzimidazole, H₂nip = 5-nitroisophthalic acid) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 is an interesting one-dimensional (1D) tube-like chain utilizing [Co₂(pbbm)₂] metallocycle as subunit. Complex 2 is also an interesting 1D tube-like chain based on [Ni₂(pbbm)₂] loop subunit. In the title complexes, the ?-? stacking and H-bonding interactions extend the 1D tube into 3D supramolecular framework, respectively. The structural differences between the title complexes indicate the importance of metal ions for the creation of molecular architectures. Furthermore, the luminescent properties of 1 and 2 were investigated.

New chloromono- and diorganotin(IV) complexes of 4-methyl-1-piperidine dithiocarboxylic acid have been synthesized in anhydrous chloroform. The complexes were characterized by microanalysis, IR, ¹H and ¹³C NMR, mass spectrometry and XRD. The FTIR spectra clearly demonstrate that organotin(IV) moieties react with [S,S] atoms of the ligand. Compound (1) and (3) exhibits the 5-coordinated while the compound (2) exhibit 6-coordinated geometry in solid state. Compound (3) shows distorted trigonal bipyramidal geometry which is confirmed by X-ray single-crystal diffraction.

Transmetalation reactions of cadmium complexes of tetraphenylporphine (CdTPP, I) and tetrabenzoporphine (CdTBP, II) in individual and mixed solvents have been investigated. For individual solvents, provided that the reaction proceeds via the same mechanism, its rate generally increases as the donor number increases in the order DMSO < DMF < PrOH-1 < MeCN (CdTPP-Zn(OAc)₂-Solv system). On passing to the CdTPP-Cu(OAc)₂-Solv system, the reaction rate order changes to DMSO < PrOH-1 < MeCN < DMF because the transmetalation mechanism changes from mixed to associative, as follows from the reaction order with respect to the salt being zero. The effect of the DMSO-DMF mixed solvent on the transmetalation reaction is limited to changing the reaction rate through alteration of the stability of the [CuX₂(Solv¹) _{n ? m ? 2}(Solv²) _m ] solvated salts. The trans effect of the ligands in the solvated salts does not increase the transmetalation rate.

A reaction of ammonium tetra(isothiocyanato)diamminechromate(III) (ammonium reineckate) with ?-caprolactam in aqueous solution at different pH values gave the novel complexes (NH₄)[Cr(NH₃)₂(NCS)₄] · 7Cpl (I), (NH₄)[Cr(NH₃)₂(NCS)₄] · 2.5Cpl · 0.5(H₂O) (II), and (HCpl₂)[Cr(NH₃)₂(NCS)₄] (III), where Cpl is ?-caprolactam (?-C₆H₁₁NO). The crystals of complexes I–III are triclinic, space group ; I: a = 12.7058(4) Å, b = 13.2544(4) Å, c = 19.4487(7) Å, ? = 105.2360(10)°, ? = 106.6410(10)°, ? = 91.5290(10)°, V = 3009.37(17) ų, ?_calc = 1.245 g/cm³, Z = 2; II: a = 12.3144(5) Å, b = 12.6518(5) Å, c = 23.3300(8) Å, ? = 75.4580(10)°, ? = 80.0760(10)°, ? = 61.0830(10)°, V = 3074.1(2) ų, ?_calc = 1.358 g/cm³, Z = 4; III: a = 6.4701(4) Å, b = 12.5973(9) Å, c = 16.5556(12) Å, ? = 108.769(2)°, ? = 98.543(2)°, ? = 90.345(2)°, V = 1261.36(15) ų, ?_calc = 1.437 g/cm³, Z = 2. The structure refinement for (HCpl₂)₃[Cr(NCS)₆] (IV) was revised. Like complex III, complex IV contains the cation (HCpl₂)⁺ stabilized by a strong hydrogen bond between the O atoms of the ?-caprolactam molecules; the cation was structurally characterized for the first time.

A new polyoxometalate-templated manganese-Schiff-base compound 1, {[Mn(L)₂]₂[PMo₁₂O₄₀][Cl] · DMF · 2CH₃CN · CH₃OH} _n (where L is 1,4-bis(4-imidazolyl)-2,3-diaza-1,3-butadiene, DMF is N,N-dimethylformamide) has been synthesized by introducing the Metal-Schiff-base into polyoxometalates(POMs) at room temperature, and structurally characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction analysis. The result of the single crystal X-ray diffraction suggested that the compound has the packing of the Mn(II)-Schiff-base cation layer and Keggin anion layer.

Extraction of Cu(II), Co(II), Ni(II), and Zn(II) with N-(para-tert-butylbenzoyl)-N?,N?-dialkylhydrazines was studied. In contrast to other listed elements, copper(II) is extracted with these reagents in a wide pH range and NH₃ concentrations, which provides its selective separation. Effect of chain length of the N?,N?-alkyl groups and solvent nature on copper extraction and its stripping conditions were determined. Extraction constants were calculated. Ammonium salts decrease the extraction degree of copper(II). The studied reagents are superior to the known industrial reagent of ?-diketone class, LIX 54, in terms of copper(II) extraction efficiency from ammonia media.

A new complex Cu(H₂L²)(H₂O)₂] (I), where H₄L² is 1,5-bis[2-(dihydroxyphosphinyl)phenoxy]-3-oxapentane, has been synthesized and characterized. Its molecular and crystal structure has been determined by X-ray crystallography and vibrational spectroscopy. In mononuclear complex I, the copper(II) cation is in a distorted square-planar environment of two water oxygen atoms and two oxygen atoms of the chelating dianion (H₂L²)^2?. The crystals are orthorhombic, space group Cmc2₁, a = 25.909(5) Å, b = 9.1500(18) Å, c = 8.5600(17) Å, V = 2029.3(7) ų, Z = 4, ?_calc = 1.688 g cm^?3, ? = 1.292 cm^?1; 3107 measured reflections, 1174 reflections with I > 2.0?(I), R _int = 0.0600, GOOF = 1.413, R ₁ (I > 2?(I)) = 0.0812, wR ₂ (I > 2?(I)) = 0.2145.

The stability constants of 1: 1 sulfate complexes (ion pairs) at 298 K are approximately calculated for all tervalent actinides and lanthanides, scandium, yttrium, and for alkali, earth-alkali, and some bivalent transition metals in aqueous solutions. The method used consists in integrating the function of the ligand distribution density with respect to a cation and allows either only solvent-separated ion pairs or all types of ion pairs to be taken into account in the calculation of constants. The dominance of solvent-separated ion pairs in infinitely dilute solutions is shown for lanthanides, actinides, and for the majority of the considered metals by comparison with experimental data.

The enthalpies of complexation of lead(II) and cobalt(II) with N-(carboxymethyl)aspartic acid (H₃Y) were determined calorimetrically at 298.15 K within a wide ionic strength range (KNO₃). The thermodynamic characteristics of formation of the CoY₂- and PbY_2? complexes were calculated at non-zero and zero ionic strengthes. The explanation of the obtained values is given.

Benzene vapor sorption by the organometallic coordination polymer [Zn₂(bdc)₂(dabco)] (H₂bdc = benzene-1,4-dicarboxylic acid, dabco = diazabicyclo[2.2.2]octane) is reported. The [Zn₂(bdc)₂(dabco)] polymer has a high C₆H₆ sorption capacity of up to 3.8 mol of benzene per formula unit. The heat of sorption has been determined, and its dependence on the composition of the inclusion compound has been investigated. Included benzene molecules are nonequivalent in terms of the energy of their interaction with the metal-organic framework.

Component interactions in the Cs₂CdBr₄-Cs₂ZnBr₄-CsBr ternary system have been studied by differential thermal analysis and X-ray powder diffraction. The liquidus surface is comprised of three crystallization fields: CsBr, a solid solution of Cs₂CdBr₄ with Cs₂ZnBr₄ (?), and a Cs₃ZnBr₅-based solid solution (?). The ternary eutectic coordinates are as follows: ?53.5 mol % Cs₂CdBr₄, 1.5 mol % Cs₂ZnBr₄, 45 mol % CsBr, and ?450°C. A Cs₂CdBr₄-Cs₃ZnBr₅ triangulating section, which is characterized by peritectic interaction with peritectic (p) coordinates of 20 mol % Cs₃ZnBr₅ and 480°C, divides the Cs₂CdBr₄-Cs₂ZnBr₄-CsBr ternary system into two ternary systems: Cs₂CdBr₄-CsBr-Cs₃ZnBr₅ and Cs₂CdBr₄-Cs₃ZnBr₅-Cs₂ZnBr₄.

Two heteronuclear germanium(IV) and lanthanum(III) (chromium(III)) complexes with 1,3-diamino-2-propanoltetraacetic acid (H₅Hpdta) have been synthesized. The compounds have been characterized by elemental analysis and X-ray powder diffraction data. The structure of [Ge(OH)(?-Hpdta)(?-OH)La(H₂O)₄] · H₂O (I) has been determined by X-ray crystallography. The crystals are monoclinic, a = 9.3805(3) Å, b = 10.3023(4) Å, c = 21.6527(6) Å, ? = 94.829(2)°, V = 2085.10(12) ų, Z = 4, space group P2₁/n, R1 = 0.0294 based on 5480 reflections with I > 2?(I). Compound I is composed of binuclear [Ge(OH)(?-Hpdta)(?-OH)La(H₂O)₄] molecules and crystal water molecules. In the dimeric molecule, the germanium and lanthanum atoms are linked by the bridging oxygen atom of the hydroxo ligand and the oxygen atom of the deprotonated isopropanol group of Hpdta^5?. The coordination spheres of germanium and lanthanum each contains one nitrogen atom and two carboxyl oxygen atoms of the four acetate arms of the heptadentate Hpdta^5? ligand. The Ge coordination polyhedron is completed to a distorted octahedron by the oxygen atom of the terminal hydroxo group, and the lanthanum coordination polyhedron is completed to a nine-vertex polyhedron by the oxygen atoms of four water molecules. In crystal, the complex molecules and crystal water molecules are combined by a system of hydrogen bonds.

Na₂CrO₄-NaF-NaI and K₂CrO₄-KF-KI three-component systems have been studied by differential thermal analysis (DTA). The compositions and melting temperatures have been determined and the enthalpies of melting have been measured for eutectic mixtures. Phase equilibria in the title systems have been described, and phase fields have been demarcated.

Selective separation of a model mixture of Cs⁺ and Cu²⁺ ions through a liquid membrane based on a 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide hydrophobic ionic liquid (IL) in the presence of chelating compounds under an electric field gradient has been studied. Modifying the hydrophobic ionic liquid membrane with a crown ether (18-crown-6 (18C6) or dibenzo-18-crown-6 (DB18C6)) provides selective separation of cesium and copper(II) ions.

Phase equilibria in the Na,K?CO₃,HCO₃,F-H₂O system at 50°C have been determined using the translation method. The system is found to be characterized by the existence of 21 divariant double-saturation fields, 19 monovariant triple-saturation curves, and six invariant quadruple-saturation points. A looped phase diagram (phase complex) for the title system at 50°C has been constructed.

We discovered that reacting Pd₃(?-OOCMe)₃ with two moles of trifluoromethanesulfonic acid (Hotf) and then with four moles of 3,5-dimethylpyrazole (Hdmpz) in acetonitrile and benzene produces, in high yields, [Pd(Hdmpz)₄](otf)₂ and Pd(Hdmpz)₄(HOOCMe)₂(otf)₂, respectively. Reacting PhenPd(OOCMe)₂ with Hotf in MeCN yields PhenPd(NCMe)₂(otf)₂, where labile acetonitrile molecules are substituted by Hdmpz under mild conditions to form PhenPd(Hdmpz)₂(otf)₂. The structures of complexes have been solved on the basis of X-ray crystallography data.

Solid solutions based on Na₇(InP₂O₇)₄PO₄ and Na₃In₂(PO₄)₃, where chromium, iron, and manganese substitute for indium, have been prepared. When chromium and iron substitute for indium in Na₇(InP₂O₇)₄PO₄, a continuous solid solution series exists. When manganese substitutes for indium, it enters the compound in the oxidation state +3. The substitution of chromium for indium in Na₃In₂(PO₄)₃ occurs within the range from 0.11 to 0.74 (mol/mol), and that of iron for indium, from 0.09 to 0.62 (mol/mol). When manganese substitutes for indium, it enters the structure of the crystalline phase in insignificant amounts as a two-charged cation.

Double vanadates of thorium and bivalent metals with r(M^II) ? 0.96 Å were prepared by high-temperature solid-phase reactions. Manganese and barium derivatives were obtained for the first time. The compounds crystallize in three structural types: zircon for manganese, cadmium, calcium, strontium, and lead derivatives; scheelite for the lead phase; and monazite for the compounds containing lead and barium. Thus, two morphotropic transitions are observed in the series of the compounds studied; and for double thorium vanadates of lead, strontium, and barium, phase transitions are observed. The bands in the IR spectra were assigned. The incongruent melting points of the compounds were determined by differential scanning calorimetry. Compounds ?-PbTh(VO₄)₂ and BaTh(VO₄)₂ were studied by high-temperature X-ray diffraction.

Complexes with cadmium-containing anions [Me₃BuN]₂⁺[CdI₄]^2? (I), [Ph₃(PhCH₂)P]₂⁺[Cd₂I₆]^2?(II), [Me₃EtN] _n ⁺[CdI₃] _n ^?(III), and [Me₃NH] _n ⁺[CdI₃] _n ^?(IV) were synthesized by reacting ammonium and phosphonium iodides with cadmium iodide. In the cations, N and P atoms have a distorted tetrahedral coordination, as Cd atom in the mononuclear [CdI₄]^2? anion of complex I, too. A centrosymmetric binuclear [Cd₂I₆]^2? anion contains two terminal (t) CdI₂ moieties linked to each other by two bridging (br) iodine atoms (Cd-I_br is 2.8547(3) Å; Cd-I_t are 2.7240(3) Å and 2.7241(3) Å). Anions of complexes III and IV are polymeric; CdI₂ structural units (Cd-I_t are 2.711(3) Å, in III and Cd-I_t are 2.7366(6) Å, in IV) are associated via iodine atoms (Cd-I_br are 2.853(3) Å in III and Cd-I_br are 2.8472(6) Å, 2,8421(6) Å in IV) to form polymer chains.

Optimal parameters of beryllium(II) sorption from aqueous solutions by polystyrene-based sorbents have been studied, namely: optimal sorption acidity (pH_opt), pH providing 50% sorption (pH₅₀), optimal time (?, min) and temperature of quantitative sorption. The sorption capacities of the sorbents under study (SCSs) for beryllium(II) have also been determined; sorption isotherms have been constructed. The parameters determined for beryllium(II) sorption by chelating polymer sorbents (CPSs) make it possible to select the most efficient sorbent for practical use.

Solutions of sodium tungstate and D-(+)-tartaric acid in aqueous 0.01 N HCl and aqueous 0.1 N NaOH are studied by polarimetry, cryoscopy, and potentiometry methods. Equations describing the dependencies of the corresponding properties on concentrations of the solution components are obtained.

The [Cu(Bcegly)(Im)](ClO₄) · H₂O aminocarboxylate, where HBcegly is N,N-bis(2-carbamoyl-ethyl)aminoacetic acid and Im is imidazole, is studied by X-ray diffraction. The polyhedron of the Cu atom is an asymmetrically elongated tetragonal bipyramid (4 + 1 + 1), whose equatorial plane is composed of two oxygen atoms (average Cu-O, 1.952 Å) and a nitrogen atom (Cu-N, 2.031 Å) of the Bcegly^? ligand and the nitrogen atom of the Im ligand (Cu-N, 1.970 Å) and the axial positions are occupied by oxygen atoms of the Bceglyligand (Cu-O, 2.357 Å) and the perchlorate ion (Cu-O, 2.830 Å). The Bcegly^? ligand fulfils the tetradentate chelate function closing three metallocycles, namely, two six-membered CuNC₃O cycles and one five-membered CuNC₂O cycle. Complex cations, ClO₄^? anions, and crystallization water molecules are connected by an extended system of hydrogen bonds.

Subsolidus phase formation in K₂MoO₄-SrMoO₄-R₂(MoO₄)₃ systems, where R = Pr, Nd, Sm, Eu, and Gd, in which KSrR(MoO₄)₃ triple molybdates are formed and crystallize in monoclinic crystal system (space group P2₁/n), have been studied using X-ray powder diffraction, differential thermal analysis (DTA), and vibrational spectroscopy. Unit cell parameters have been determined for these molybdates; their IR and Raman spectra are reported.

The solubility in the quaternary water-salt systems LaCl₃-NdCl₃-HCl-H₂O (1) and LaCl₃-PrCl₃-HCl-H₂O (2) at 25°C was studied in the section of 40 wt % hydrochloric acid, a system with a eutonic discontinuity. The composition at the point of discontinuity for the eutonic solution is the following. In system 1: 4.67 wt % LaCl₃ · 7H₂O, 0.37 wt % PrCl₃ · 7H₂O, 37.98 wt % HCl, and 56.98 wt % H₂O; in system 2: 4.37 wt % LaCl₃ · 7H₂O, 0.93 wt % NdCl₃ · 6H₂O, 37.88 wt % HCl, and 56.82 wt % H₂O.

The crystal structure of the EuLaCuS₃complex sulfide synthesized for the first time has been solved by X-ray powder diffraction. Crystals are orthorhombic, space group Pnma, Ba₂MnS₃-type structure, a = 8.1297(3) Å, b = 4.0625(1) Å, c = 15.9810(4) Å, V = 527.80(3) ų, Z = 4, and ?_calc = 5.669 g/cm³. The La and Eu atoms are randomly disordered over two crystallographic positions with a coordination number of 7, and the Eu(La)-S bond lengths range from 2.892(6) to 3.078(6) Å. The CuS₄ tetrahedra with Cu-S interatomic distances of 2.358(5)–2.40(1) Å form chains running along the b axis.

The reaction of ammonium chloride with zinc oxide was studied kinetically and thermogravimetrically. Reaction products were identified by IR spectroscopy and X-ray powder diffraction. Ammonium chlorozincates were found to form in the reaction and to decompose to zinc chloride.

The extraction ability of the organic salt of acidic phosphoryl podand (1,5-bis(o-(hydroxyethoxyphosphoryl)phenoxy)-3-oxapentane) and trioctylamine with respect to cesium in nitric acid and carbonate media is investigated. The extraction ability of the organic salts of acidic phosphoryl podand and trioctylamine are compared to those of dibenzo-18-crown-6 and di-tert-butyldicyclohexano-18-crown-6. It is shown that organic salts of this type have a significant advantage in the extraction of cesium from nitric acid and carbonate solutions.

A bismuth(III) complex of N-methylthiourea (Mtu, C₂H₆N₂S) [Bi(C₂H₆N₂S)₆](ClO₄)₃ has been synthesized, and its crystal structure has been determined. The structure is built of octahedral Bi(Mtu)₆³⁺ cations and ClO₄^? anions. Sulfur atoms are coordinated to bismuth(III) (at axis 2) at octahedron vertices (Bi-S, 2.7670(8), 2.8142(8), and 2.8315(8) Å); angles SBiS vary from 82.26(3)° to 96.13(2)°. The presence of amino groups and oxygen atoms in the structure results in the emergence of numerous hydrogen bonds (HBs). All H atoms of amino groups are involved in HBs; one of them is bound to the sulfur atom. One of the oxygen atoms of ClO₄^? anions does not participate in HBs.

The formation constants of bismuth(III) methylthiourea complexes in aqueous solution were determined at 298 K and an acidity of 2 M HClO₄ using the “ligand-oxidized ligand species” potentiometric method and the methylthiourea (mtu)-symmetric dimethylformamidine disulfide (mFDS) redox pair. The formation function was obtained, and the conditional (? _n ^*) and true (? _n ) formation constants of Bi(mtu) _n ³⁺ (1 ? n ? 8) were calculated. The value of ?₁ and the formation of complexes with coordination numbers higher than six was confirmed by spectrophotometry.

Vapor pressure as a function of temperature above solid and liquid (BrBNH)₃ and the thermodynamic parameters of (BrBNH)₃ sublimation and vaporization have been determined using static tensimetry with membrane null-manometer. The thermal decomposition of tribromoborazine has been studied in the saturated and unsaturated vapor regions. Irreversible decomposition occurred at noticeable rates at temperatures higher than 343 K and was accompanied by HBr evolution. In the unsaturated vapor region, thermal decomposition has far lower rates than in the saturated vapor region because of diffusion limitations. The activation energy of condensed-phase thermal decomposition of B,B?,B?-tribromoborazine is 65 ± 3 kJ/mol, and this value proves that tribromoborazine decomposition at low temperatures is not accompanied by opening of the boron-nitrogen cycle.

A reaction of aqueous zinc acetate with 1,10-phenanthroline produces the ionic complex [(Phen)₂Zn(OOCMe)](OOCMe) · 5H₂O. A similar reaction of “anhydrous zinc acetate” [Zn₇(?₄-O)₂(?-OOCMe)₁₀][?-OC(Me)OHNEt₃]₂ in benzene yields a precipitate, which is recrystallized from acetonitrile into trinuclear (Phen)₂Zn₃(?-OOCMe)₆; and the reaction in acetonitrile yields mononuclear (Phen)Zn(OOCMe)₂ · MeCN. These complexes have been characterized by single-crystal X-ray diffraction.

Solubility of the CsH₂PO₄-CsHSO₄-H₂O system has been studied using the isothermal method (25.0°C); the compounds Cs₄(HSO₄)₃(H₂PO₄), Cs₃(HSO₄)₂(H₂PO₄), and Cs₅(HSO₄)₂(H₂PO₄)₃ have been found to form; Cs₅(HSO₄)₂(H₂PO₄)₃ has been obtained for the first time. Single crystals of the isolated phases have been grown. Their composition has been determined, and agreement between the results of studying solid phases in the CsH₂PO₄-CsHSO₄-H₂O and these single-crystal samples has been demonstrated. X-ray diffraction analysis of these phases has been carried out.

Titanium dioxide nanoparticles were employed for the sorption of Ge(IV) ions from aqueous solution. The process was studied in detail by varying the sorption time, pH, and temperature. The sorption process was found to be fast, equilibrium was reached within 3 min. A maximum sorption could be achieved from solution when the pH ranges between 4.0 and 11.0. Sorbed Ge(IV) ions can be completely desorbed with 2 mL of 0.3 mol L^?1 K₃PO₄-1.0 mol L^?1 H₂SO₄ mixture solution. The kinetic experimental data properly correlate with the second-order kinetic model (k ₂ = 0.88 g mg^?1 min^?1 (25°C)), Reichenberg equation and Morris-Weber model. The estimated E _a for Ge(IV) adsorption on nano-TiO₂ was 19.66 kJ mol^?1. The overall rate process appears to be influenced by intra-particle diffusion. The sorption data could be well interpreted with the Langmuir and Dubinin-Radushkevich (D-R) type sorption isotherms. The D-R parameters were calculated to be K = ?0.00321 mol₂ kJ^?2, q _m = 0.59 mmol g^?1 and E = 12.48 kJ mol^?1 at room temperature. Furthermore, the thermodynamic parameters were also determined, and the ?H ⁰ and ?G ⁰ values indicated a spontaneous exothermic behavior.

A new method of synthesis of the B₃H₈^? anion has been suggested. The method uses the reaction of some metal halides (CuCl, SnCl₂, CrCl₃, PbF₂, PbCl₂, PbBr₂, and BiCl₃) with sodium tetrahydroborate. It is characterized by high (up to quantitative) yields and simplicity of isolation of the target products ((n-C₄H₉)₄N)[B₃H₈] and Cs[B₃H₈].

The interaction of bismuth(III) oxide with formic acid solutions at 22 and 55°C was studied using X-ray powder diffraction, thermogravimetry, electron microscopy, IR spectroscopy, and chemical analysis. Solubility curves were found to comprise two branches due to formates of compositions Bi(COOH)₃ and BiOCOOH forming in the system. Thermal decomposition of bismuth formates is shown to be a promising route for the synthesis of metallic bismuth, as well as of tetragonal (?) and monoclinic (?) bismuth oxides.

Phases with with a NiAs-based structure have been studied in Au-Pd-Sn and Cu-Pd-Sn systems at 500°C using powder X-ray diffraction, X-ray structure analysis, and energy-dispersive X-ray microanalysis. In the Cu-Pd-Sn system, binary phases ?-Pd₂Sn and Cu6Sn5 both having the Ni2In structure form a phase region (Pd,Cu)_{2 ? x} Sn, which preserves the Ni₂In structure and is confined at 500°C by an L + (Pd,Cu)_{2 ? x} Sn + ?-Cu₃Sn three-phase region. In the Au-Pd-Sn system, the ?-AuSn phase with the NiAs structure and ?-Pd₂Sn with the Ni₂In structure form a single phase region (Pd,Au)_{2 ? x} Sn, which is bounded at 500°C by an L + (Pd,Au)_{2 ? x} Sn two-phase region; the structure of the ternary phase changes from Ni2In with incompletely filled trigonal-prismatic interstices to NiAs. The Pd₂₀Sn₁₃ phase, which crystallizes in the GaGe₂Ni₄ type structure, penetrates into both ternary systems up to ?5 at % of the third component. The solubilities of copper and gold in PdSn and Pd₂Sn phases, which have structures based on orthorhombically distorted NiAs and Ni₂In lattices, respectively, do not exceed 2 at %.

Gibbs energies of formation have been determined by conductometric titration for hydroxo complexes of cerium, samarium, europium, erbium, ytterbium, and yttrium. All these elements form monohydroxo complexes; yttrium, erbium, and terbium also form dihydroxo complexes. The Gibbs energies of formation of lanthanide hydroxo complexes from ions have virtually equal values of ?47.3 ± 0.6 kJ/mol monohydroxo complexes and ?44.5 ± 0.5 kJ/mol for dihydroxo complexes, respectively. These values were used to estimate the Gibbs energies of formation of hydroxo complexes for the entire lanthanide series.

The theory of elasticity and crystal lattice dynamics methods were used to elucidate specific features of chemical bonding in zinc crystals, which extends the possibilities of solving materials science problems.

The potential energy surfaces of elementary reactions of dissociative addition of one and two H₂ molecules to Cr-, Mo-, or W-doped aluminide clusters MAl12 in the states of different multiplicity have been calculated by the density functional theory method. The results are compared with the previous calculations of analogous reactions involving the singlet and triplet TiAl₁₂ cluster. The effect of the dopant nature and electronic state multiplicity on the energies and activation barriers of hydrogenation reactions is considered.

The compound [Cu(TSC)₂](H₂SSal)₂ (I) has been synthesized (TSC is thiosemicarbazide, H₃SSal is 5-sulfosalicylic acid) and studied by IR spectroscopy and X-ray crystallography. The crystals of I are triclinic: a = 6.728(2) Å, b = 7.772(1)Å, c = 11.600(6)Å, ? = 88.60°, ? = 86.68(3)°, ? = 79.22(4)°, V = 594.8(4)ų, Z = 2, space group . The structural units of the crystal are the centrosymmetric [Cu(TSC)₂]²⁺ cation, in which the Cu atom is in a square-planar coordination formed by the bidentate chelating (N,S) TSC ligands, and (H₂SSal)^? anions (Cu(1)-N(3), 2.013(3) Å; Cu(1)-S(1), 2.275(1) Å). The coordination polyhedron of the Cu(1) atom is completed to a prolate tetragonal bipyramid (4 + 2) by Cu-O bonds (2.810(3) Å) of the sulfate moieties of both anions, which form together with hydrogen bonds the [Cu(TSC)₂(H₂SSal)₂] supermolecule. The complex cations are packed in layers and alternate with anion-containing layers. Hydrogen bonding and ??? stacking interactions are responsible for formation of supramolecular layer ensembles.

Phase equilibria in Li₂SO₄-KLiSO₄-H₂O and K₂SO₄-KLiSO₄-H₂O ternary systems, which contain type 2 salts (Li₂SO₄, KLiSO₄, and K₂SO₄), were studied at temperature of 380 to 400°C and pressures up to 90 MPa. Homogeneous supercritical (SC) fluids, which propagate from type 2 water-salt subsystems into a three-component region, change to heterogeneous liquid-phase equilibria as a result of the transformation of metastable immiscibility regions into stable equilibria. The heterogenization of SC fluids starts with critical phenomena in saturated solutions. In the K₂SO₄-KLiSO₄-H₂O system, the monovariant critical curve reveals a temperature maximum at the invariant double critical end point (DCE).

The equilibria in binary and ternary systems containing a nickel(II) salt, 2-hydroxyethyliminodiacetic acid, and dicarboxylates were studied by spectrophotometric and potentiometric methods with NaClO₄ as the supporting electrolyte at I = 0.1 and T = 20 ± 2°C. The molar and protic composition and the pH regions of existence of the complexes were determined, the stability constants of complexes containing the same or different ligands were determined. The fractional distribution of the complexes as the function of acidity was elucidated. The experimental data were treated using mathematical models to estimate the possibility of existence of a broad range of complex species in solution and to distinguish the species that are sufficient to take into account for reproducing the experimental results.

A low-temperature method has been developed for preparing nickel ferrite doped with cobalt and copper (Ni_0.9Co_0.1Cu_0.1Fe_1.9O_{4 ? ?}). This method provides the target product at 170–200°C with nanosized particles. The role of ammonium nitrate in the considerable reduction of ferrite synthesis temperature was studied.

Mixed-ligand complexation of yttrium subgroup lanthanide ethylenediaminetetraacetates with asparaginate, iminodiacetate, and nitrilotriacetate ions in aqueous solution was studied by calorimetry and pH-metry. The full set of thermodynamic parameters (logK, ? _r G ₀, ? _r H, ? _r S) of the addition reactions of Asp^2?, Ida^2?, and Nta^3? to LnEdta^? (Ln³⁺ = Tb³⁺, Dy³⁺, Ho³⁺, Er³⁺, Tm³⁺, Yb³⁺, Lu³⁺) was determined at 298.15 K and ionic strength I = 0.5(KNO₃). The change in the thermodynamic parameters of the reactions over the series of lanthanides was discussed.

The results of static magnetic susceptibility studies of spacer-armed dinuclear copper(II) complexes with dicarboxylic acid acylhydrazones are described. Weak exchange coupling between paramagnetic centers has been detected with an exchange parameter value of ?2J ? 1–7 cm^?1. Short intermolecular contacts give rise to additional weak antiferromagnetic exchange coupling between copper cations comparable in terms of energy with superexchange inside the dinuclear complex (?zJ? ? 0.6–5.0 cm^?1).

Processes that take place during extraction of HAuCl₄ from hydrochloric acid solutions with neutral oxygen-containing extractants (esters, ethers, and ketones) were considered. Distribution ratios for certain extractants were determined. Separation factors ?_Au/M (M = Fe, Ag) were shown to exhibit low change upon extractant variation. For example, when D _Au changes by 6 orders of magnitude, the maximum deviation from log?_Au/Fe = 3.5 is not larger than 0.5, average s = 0.2.

Covalent bonding of polyhexamethyleneguanidine amides of maleic and o-phthalic acids to the aminated silica surface was performed. The complexing properties of the obtained composite adsorbents with respect to Zn(II), Cu(II), Fe(III), Co(II), Pb(II), Ni(II), Mn(II), Mo(VI), and Cr(VI) ions were studied. The Mo(VI) and Cr(VI) reduction was detected on the modified silica surface bearing polyhexamethyleneguanidine amide with o-phthalic acid. The formation of different-ligand complexes with transition metal cations adsorbed on the synthesized composite surface was studied.

CoMoO₄nanoscale materials were synthesized by a facile coprecipitation method and annealed at different temperatures with significant alteration of morphologies. The obtained CoMoO₄ materials were characterized by X-ray diffraction (XRD), FTIR spectroscopy, thermogravimetry and differential scanning calorimetry (TG-DSC) and scanning electron microscopy (SEM).

The stability constants of the cesium complexes [Cs(DB21C7)]⁺ and [Cs(DB24C8)]⁺, where DB21C7 = dibenzo-21-crown-7 and DB24C8 = dibenzo-24-crown-8, in the hydrophobic ionic liquid 1-butyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide ([BMIM][N(Tf)₂]) have been measured by ¹³³Cs NMR spectroscopy between 24 and 54°C. The enthalpies and entropies of complexation have been determined. For [Cs(DB21C7)]⁺ and [Cs(DB24C8)]⁺ at 25°C, log K ₁ = 3.52 (0.01) and 2.91 (0.04), ?H ₁ = ?27 (1) and ?7 (6) /mol, and ?S ₁ = ?23 (3) and 33 (20) J/(mol K), respectively.

Modeling of atomic species (An clusters in the form of atoms or Kn polyhedra, where n is the number of atoms or polyhedra) corresponding to the initial stage of evolution of a chemical system has been carried out. Three series of K4 clusters built of different T tetrahedra (L and T) have been recognized. For L₂T₂ clusters, six geometrically and symmetrically different types of suprapolyhedral clusters have been discovered. The model has been used to identify precursor clusters in A₂T₂O₅ (A = Li, Na; T = Si, Ge) framework structures: A-type Li₂T₂O₅ with space group Cc, B-type Li₄Ge₃SiO₁₀ with space group Abm2, C-type Li₂Si₂O₅ with space group Ccc2, and D-type A₂Si₂O₅ with space group Pbcn. Three (of the six possible) types of suprapolyhedral precursor nanoclusters K4 in the four structures have been identified. The full 3D reconstruction of the self-assembly scenario of crystal structures is as follows: precursor nanocluster ? primary chain ? microlayer ? microframework ? … framework. The bifurcation of structural evolution pathways (structural branching points) at the suprapolyhedral level for type A and B structures is found to occur only when a microframework is formed of equivalent microlayers.