Structural,spectroscopic, and thermophysical investigations of the oxyfluorides CsZnMoO3F3 and CsMnMoO3F3 with the pyrochlore structure

The structure, infrared and Raman spectra, heat capacity, and thermal expansion have been investigated. It has been shown that, down to liquid-helium temperatures, the cubic pyrochlore structure of the CsMnMoO₃F₃ and CsZnMoO₃F₃ oxyfluorides remains stable. The influence of cation substitution on individual features of the properties of the oxyfluorides has been analyzed.     

The role of carbon support morphology in the formation of catalytic layer of solid-polymer fuel cell

The Pt/C catalysts with similar morphology of active catalytic phase (platinum nanoparticles), which were deposited on the supports with different types of carbon structures (Vulkan XC-72 carbon black, Taunit carbon tubes, and Timrex HSAG-300 carbon support with graphite structure), were fabricated by the method of electrochemical dispersion. The effect of the carbon structure type on the electrocatalytic properties of Pt/C catalysts was studied in their operation in the three-electrode cell and in-service in the membrane-electrode assembly of air-hydrogen solid-polymer fuel cell. The Pt/C catalyst based on the Vulkan XC-72 carbon support showed the best performance. The anisotropic shape of Taunit carbon nanotubes and the microstructure of Timrex HSAG-300 carbon support do not allow us to form a catalytic layer with a large active platinum surface area and a structure, which provides an effective ionic transport and mass exchange near the platinum surface.     

Metal derivatives of diterpenoid isosteviol

Metal salts (including transition metals salts) of chiral natural diterpenoid isosteviol and its hydrophosphoryl derivative were obtained for the first time. The compounds obtained can be used in pharmaceutics, metal catalysis, and also for creating new materials with magnetic properties.     

Phase equilibria in the iodine-potassium iodide-water-propanol-2 four-component system

Isothermal-isobaric sections of the phase diagram of the iodine-potassium iodide-water-propanol-2 (2-C₃H₇OH) four-component system were studied at 25°C and atmospheric pressure. In all sections, threephase eutonic equilibria were observed with potassium iodide and crystalline iodine as solid phases. Potassium iodide was a iodine salting in agent in sections containing 15 and 25 wt % propanol-2 and a salting out agent in the section with 50 wt % alcohol. H₂O-2-C₃H₇OH (85: 15 and 75: 25 wt %) mixed solvent compositions showed a higher ability to dissolve iodine than mixture components.     

Electronic structure of the conduction band of the interface region of ultrathin films of substituted perylenedicarboximides and the germanium oxide surface

The results of the investigation of the electronic structure of the conduction band and the interfacial potential barrier during the formation of interfaces of dioctyl-substituted perylenedicarboximide (PTCDI-C₈) and diphenyl-substituted perylenedicarboximide (PTCDI-Ph) ultrathin films with the oxidized germanium surface have been presented. The experimental results have been obtained using the very low energy electron diffraction (VLEED) technique in the total current spectroscopy (TCS) mode at energies in the range from 5 to 20 eV above the Fermi level E_F. The positions of the maxima of the fine structure of total current spectra (FSTCS) of the PTCDI-C₈ and PTCDI-Ph films differ significantly in the energy range from 9 to 20 eV above the Fermi level E_F, which can be associated with the difference between the substituents of the chosen molecules, dioctyl- and diphenyl-, respectively. At the same time, the positions of the lowenergy maxima in the FSTCS spectra at an energy 6–7 eV above the Fermi level E_F for the PTCDI-C₈ and PTCDI-Ph films almost coincide with each other. It has been suggested that these maxima are attributed to the electronic states of the perylene core of the molecules under investigation. The process of the formation of interfacial potential barriers of the PTCDI-C₈ and PTCDI-Ph films with the oxidized germanium surface has been analyzed. It has been found that the work functions of the surface, E_vac–E_F, differ little from 4.6 ± 0.1 eV over the entire range of organic coating thicknesses from 0 to 6 nm.     

A study of complexation between crystalline <Emphasis Type="Italic">trans</Emphasis>-[Pd(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>(NO<Subscript>3</Subscript>)<Subscript>2</Subscript>] and acetylacetone

Complexation between crystalline trans-[Pd(H₂O)₂(NO₃)₂] and acetylacetone was studied. The complexes Pd₂(Acac)₂(μ-NO₃)₂(I) and Pd₂(Acac)₂(μ-Acac)(μ-NO₃)(II) were obtained and examined by elemental analysis, X-ray powder diffraction analysis, differential scanning calorimetry, simultaneous thermal analysis, mass spectrometry, and vibrational spectroscopy.