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The salt [NH3(CH2)2SS(CH2)2NH3][CuCl4] was obtained by crystallization after adding CuCl2to cystamine (Cysta), solved in hydrochloric acid. The assumption of conserved disulfide connection (S–S) in the compound, made on the basis of infrared spectroscopy, is further supported by the crystal structure determined from X-ray powder diffraction data. The compound has an ionic structure. [CuCl4]2-and CystaH22+ions package in the form of inorganic and organic layers in the cell, interconnected through the formation of hydrogen bonds via NH3-groups and chlorine atoms of the complex [CuCl4]2-. Inorganic layers are additionally stabilized in the parquet package of [CuCl4]2-ions which provides a Cu-distorted octahedral coordination. CystaH2[CuCl4] is stable in air up to 200 °C. Thermal decomposition occurs in several stages, accompanied by breaking of S–S bonds, releasing of the organic component and yielding CuO.

The temperature dependence of the molar heat capacity of Y2Cu2O5has been measured at 328–953 K. The thermodynamic functions of the oxide compound have been calculated from the experimental data.

The heat capacity of Gd2CuO4has been studied by differential scanning calorimetry in the temperature range 362–958 K. It has been found that the temperature dependence of the molar heat capacity has an extremum near 590 K; the extremum is related to a phase transition from the high-temperature tetragonal phase to the low-temperature orthorhombic phase.

The heat capacities of Sm2CuO4and Ho2Cu2O5have been measured in the temperature ranges 329–839 and 359–751 K, respectively. The experimental data have been used to determine the thermodynamic properties of the oxide compounds.

The heat capacity of La2CuO4has been measured in the temperature range 400–950 K. The temperature dependence of the heat capacity has been found to exhibit an extremum at 526 K.

The formation of a mesostructured silicate material of the MCM-41 type is studied. The influence of the replacement of components in a reaction medium is investigated experimentally. Analysis of the results obtained and the data available in the literature suggests that the process under investigation is based on the approximate stoichiometric supramolecular interaction between [Si4O4 + x(OH)9 − x]−(1 + x)silicate polyanions and C16H33(CH3)3N+cetyltrimethylammonium cations with the formation of supramolecular aggregates, which condense to a mesostructured organosilicate composite. A further evolution of the product involves hydrolysis of the inner surface and the polymerization of the inorganic component. It is demonstrated that the properties of the product are determined, to a large extent, by the components of the reaction medium, which control the relative reaction rates in the process. The inference is made that an alcohol-ammonia medium is the most optimum for alkaline synthesis. This medium provides good preparation of the initial components for the reaction and the high rate of hydrolysis of pore walls, minimizes the osmotic effects during hydrothermal treatment, and, eventually, favors the formation of a highly structured hydrothermally stable material.

An X-Ray powder diffraction study of ultra-dispersed polytetrafluoroethylene was carried out. As well as a regular polytetrafluoroethylene the ultra-dispersed form contents a high proportion of the crystalline phase. The X-ray diffraction pattern could be described with two-dimensional hexagonal unit cell [a=5.685(1) ?, symmetry group p6mm]. Structural modeling with a continuous electron density approach as well as with a discrete disordered atoms distribution was accomplished. The model was refined using the Rietveld method. The structure is characterized by a spiral arrangement of polymers (CF2-)nalong the z-axis with complete mutual disordering by rotational displacement around z, as well as a partial molecular translation along the z-axis. Molecular disordering results in a systematic absence of reflections with 1?0 and as a sequence in two-dimensional unit cell effect. The presence of complete rotational disordering distinguishes the ultra-dispersed form of polytetrafluoroethylene from the standard one (fluoroplast-4), where only partial disordering is observed.

A new palladium compound [Pd(NH3)4][cis-Pd(NH3)2(SO3)2][Pd(NH3)3(SO3)] · H2O (I) was synthesized and its structure was studied by X-ray powder diffraction method. In the course of the synthesis, the initial trans-diamminesulfite anionic complex is transformed into the cis-configuration. Further heating in aqueous solution results in isomerization of a substance into a neutral complex [Pd(NH3)3(SO3)]. Crystals Iare triclinic: a= 10.3297(2) Å, b= 14.1062(3) Å, c= 6.8531(1) Å, α = 101.36(0)°, β = 92.74(0)°, γ = 92.71(0)°, space group P1¯. Structure Iconsists of the columns with alternating cis-[Pd(NH3)2(SO3)2]2–and [Pd(NH3)3(SO3)] complexes and [Pd(NH3)4]2+ions between the columns.

The formation of the structure of a highly organized silicate mesoporous mesophase material (MMM) with hexagonal packing via the S+I–reaction pathway and MMM-based aluminosilicates (Al,Si)-MMM and titanosilicates (Ti,Si)-MMM with different concentrations of the elements are considered. The structural, textural, and catalytic properties of the materials are studied.

A compound previously reported as HAlF4 has been shown to be [pyridinium][Al3F10]. The structure of this phase was solved and refined using a combination of synchrotron X-ray and neutron powder diffraction techniques in association with a number of other analytical techniques. The structure consists of [Al3F10]n^- sheets containing both corner-sharing (common) and edge-sharing (unusual) AlF6 octahedra. The sheets are separated by pyridinium cations oriented perpendicular to the sheets. The final crystallographic data are as follows:  monoclinic, space group C2/m, a = 8.2706(3), b = 6.1998(3), c = 10.525(1) Å, β = 103.38(1)°, V = 525.0(1) ų, and Z = 2. This compound appears to be another example of a layered “clay-like” aluminum fluoride.

Without Abstract:

Sulfur dioxide is adsorbed on zeolites Y in two forms. The amount of the stable form (Tdes=350–390 K) changes in proportion to the sodium content in the zeolite The stable form is localized in a large void at a distance of ~1.8 å from the SII position and causes redistribution of sodium cations. The weakly bound form (Tdes=286–300 K) makes the main contribution to the adsorption of SO2 on highly siliceous zeolites Y and is formed by adsorbate-adsorbate interaction, and it is apparently delocalized in a large void. Out-of-framework aluminum compounds that are formed during dealumination decrease the free volume of the zeolite without changing the nature of interaction of SO2 with the zeolite.

Dealumination of type Y zeolite using SiCl4 produces a statistically averaged distribution of Al and Si atoms in the framework. The action of H4EDTA causes defects in the backbone and partial amorphization of the zeolite. Extracellular particles containing Al form due to dealumination with SiCl4. The maximum number of these occurs at nalbb=5–16 atoms/unit cell. Treatment with H4EDTA has practically no effect on the composition of the particles, which are largely sodium cations. The extracellular particles localize both in sodalite cells and in large voids after dealumination with SiCl4.

X-ray powder diffraction analysis of the crystal structure of hexagonal MoO3 indicates that this structure is observed for AxMexMoX-xO3 compounds, where A=NH4, K, Rb, Cs, Me=V, P, Sn, Ti, Zr, Si.

Trans-Pd NH3)2Cl2was studied by powder diffractometry. The unit cell parameters are a = 6.5408(8), b = 6.8573(8), c = 6.3574(6) Å, a = 103.303(5), Β = 102.457(3), γ = 100.612(4); V = 262.63 Å3, Z = 2, space group. The atomic coordinates were established from Patterson syntheses and refined by the Rietveld method: Rp= 10.7%, Rwp= 10.2%, Rexp= 5.6%, RB= 3.6%. The crystal structure is of molecular type. The planar trans-Pd(NH3)2Cl2molecules are packed parallel to each other into columns along the z axis, with every next molecule rotated through an angle of ∼ π/2. The observed packing of columns reproduces the cis-isomer quite closely. The structure has a disordering at 0.1Pd positions at 1/2, 0, 0 and 1/2 1/2, 0. A possible explanation for the nature of additional positions is offered.

The crystal structure of [Pd(NH3)4]C2O4was determined from X-ray powder data. The crystals are triclinic with unit-cell parameters: a=7.0807(7) ?, b=7.0806(7) ?, c=3.8011(5) ?, ?=91.910(1)?, ?=98.665(1)?, ?=97.283(1)?, S.G.=P?1, Z=1, V=187.11 ?3. All non-hydrogen atoms were located from the Patterson map. The structure was refined by the Rietveld technique: Rp?b=6.88, Rwp=6.51, RB=2.66. The crystal structure of [Pd(NH3)4]C2O4is built from two types of elements: [Pd(NH3)4]2+and C2O2?4. Cations [Pd(NH3)4]2+form columns along cwith distances (Pd?Pd)=3.8011 ?. C2O2?4anions occupy places in the middle of the unit cell between layers of [Pd(NH3)4]2+. The compound is stable up to 200 ?C and then decomposes, giving Pd powder.

X-ray diffraction, XPS, and NMR have been used to investigate the nature and centers of localization of nonframework particles in Y zeolite dealuminated by silicon tetrachloride. It has been established that the reaction products formed upon dealumination consist mainly of aluminum compounds that migrate from the volume of the zeolite to the surface and are also partially localized in internal supercages and small cages (sodalite cells). Water washing removes the particles localized in the supercages but does not affect the particles localized in sodalite cells. It has been shown that, by plotting maps of electron density on the basis of x-ray powder diffraction patterns, the sites of localization of extraframework particles can be determined. The results are consistent with those obtained by other methods, and the maps of electron density give a graphic picture of changes in internal structure of the Y zeolite.

Experimental data on the molar heat capacity of Lu2Cu2O5in the temperature range 366–992 K have been obtained. The experimental data have been used to calculate the thermodynamic properties of the oxide compound.

The molar heat capacity of Tm2Cu2O5has been studied using differential scanning calorimetry in the temperature range 431–1004 K. The thermodynamic functions of the solid oxide compound have been calculated from the experimental data Cp= f(T).

The heat capacity of Tb2Cu2O5in the temperature range 379–924 K has been measured using differential scanning calorimetry. It has been shown that the obtained dependence Cp= f(T) can be described by a combination of the Debye and Einstein functions.

Data on the heat capacity of Dy2Cu2O5in the temperature range 346–981 K have been obtained. The experimental data have been used for determining the thermodynamic properties of this oxide compound.

Experimental data on the heat capacity of CuGa2O4in the range 329–1050 K are presented. The values of the thermodynamic functions (enthalpy and entropy changes) are calculated from smoothed values of the heat capacity.

Abstract: The heat capacity of Bi2CuO4 has been measured over a wide temperature range. The thermodynamic functions of the solid oxide compound have been calculated using the experimental data.

Abstract: The temperature dependence of the heat capacity of Bi2Al4O9 has been studied. The values of the thermodynamic functions (changes in the enthalpy and entropy) have been calculated from the smoothened values of the heat capacity.

Seven new phases containing hexachloroplatinate [PtCl6]2− and trans-1,2-dl-diammoniumcyclohexane 1,2-C6H10NH322+ ions were obtained by crystallization from solutions with minor variation of synthesis conditions. The compounds can be applied as precursors for the synthesis of effective anticancer drug tetraplatin ([PtC6H10(NH2)2Cl4]). The phase diversity was achieved by alterations including solvent acidity, crystallization rate, temperature, type of solvent, and the reagents ratio. The compounds were characterized by chemical and thermal analysis, IR, and 1H NMR spectroscopy. Crystal structures of the five compounds were determined by X-ray powder diffraction technique. The phases have ionic structures involving H2O, HCl molecules, or Cl− ions as supplementary species in the lattices. It helps to arrange some frames additionally interconnected by hydrogen bonds between ions and solvent molecules. It was suggested that crystal lattices adapted associated particles presented in solutions. It results in observed variety of the crystal structures. Besides the basic interest the obtained results are important for tetraplatin synthesis control.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.