Reaction of H2PtCl6 with 18-crown-6 and dibenzo-18-crown-6 in 1,2-dichloroethane and acetonitrile

Compounds of the compositions [2(18-crown-6)6(H₂O)2(C₂H₄Cl₂){Pt²⁺(C₂H₄)}(Pt₂Cl₁₀)^2–], [4(18-crown-6)2(OH₃)⁺2(OH₂)2(NH₃)(Pt₂Cl₁₀)^2–], [(dibenzo-18-crown-6)6(H₂O){Pt²⁺(C₂H₄)}(Pt₂Cl₁₀)^2–], and [4(dibenzo-18-crown-6)2(OH₃)⁺2(OH₂)2(NH₃)Pt₂Cl₁₀)^2–] were prepared by reactions of H₂PtCl₆ with 18-crown-6 and dibenzo-18-crown-6.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1593–1599.Original Russian Text Copyright © 2004 by Guseva, Busygina, Khasanshin, Polovnyak, Yarkova, Yusupov.This revised version was published online in April 2005 with a corrected cover date.     

Reaction of rhodium trichloride with oxyethylated calix[4]resorcinarene

Reaction of rhodium trichloride with a new ligand, oxyethylated calix[4]resorcinarene was examined in an inert atmosphere in different solvents (acetone, acetone + chloroform). The product was characterized by IR, Raman, ¹H NMR, ESR, ESCA spectroscopy, conductometry. Its composition was proved by the data of elemental and X-ray fluorescent analyses. The solvent used does not affect the composition of the product but only its yield. The structure of the coordination node and the type of coordination of the rhodium-containing fragment was investigated by calculating the model molecules of the ligand and the complex using the molecular mechanics method (MM+).     

Complex Formation of Potassium Hexachloroplatinate with 18-Crown-6 and Dibenzo-18-Crown-6 in Acetonitrile

The products of the reactions between potassium hexachloroplatinate {K₂PtCl₆} and 18-crown-6 or dibenzo-18-crown-6 in acetonitrile were studied. Pure crystalline compounds [2K·2(18-crown-6)· 2CH₃CN]²⁺·[PtCl₆]^2-·2H₂O, [2K·dibenzo-18-crown-6·CH₃CN]^{2 +}·[PtCl₆]^{2 -}, and [2K·dibenzo-18-crown-6·CH₃CN]^{2 +}·[Pt₂Cl₁₀]^{2 -} were obtained. Physicochemical properties of these compounds were studied, and their near- and far-IR IR spectra and thermogravimetric curves were considered. The composition of the complexes is determined by metal:ligand molar ratio and crown ether nature. It was found that acetonitrile is coordinated via the nitrogen atom.     

Changes in the optical properties of the functional surfaces of spacecraft exposed to both electron and UV action

The results of an experimental investigation into the effect of photoradiation action (UV and electrons of 45 keV) on the optical properties of quartz glass and hydrocarbon contaminant films deposited onto it are presented. It is revealed that the transmittance of solar radiation by contaminated glasses significantly decreases under the action of radiation simulating real space conditions. It is shown that the optical properties of the films degrade due to the formation of additional absorption centers of electromagnetic radiation, and the process occurs with saturation. The coefficient of solar radiation attenuation is determined for the irradiated films formed by degassing products from the EKOM-1 polymer material.     

Effect of residual atmospheric pressure on the development of electrostatic discharges at the surface of protective glasses of solar cells

Electrostatic discharges obtained upon the irradiation of K-208 glass with 40-keV electrons at a flux density φ of 10¹⁰ to 2 × 10¹¹ cm^–2 s^–1 are studied. The residual pressure p _v in the vacuum chamber is varied from 5 × 10^–5 to 5 × 10^–3 Pa. Structural changes in the sample surfaces are studied by atomic-force microscopy. Depending on the pressure level, two types of discharges are observed in experiments at 3 × 10¹⁰ ≤ φ ≤ 1.2 × 10¹¹ cm^–2 s^–1: a microprojection at the glass–ionized-residual-atmosphere surface and a discharge which develops along the irradiated surface. It is found that at 5 × 10^–5 ≤ p _v ≤ 3 × 10^–4 Pa and 8 × 10¹⁰ ≤ φ ≤ 10¹¹ cm^–2 s^–1, discharges of the first type appear at the beginning of exposure; that is, an increase in microprojections is observed. Further, surface discharges propagate through these microprojections. At 10^–3 ≤ p _v ≤ 5 × 10^–3 Pa and 10¹⁰ ≤ φ ≤ 5 × 10¹⁰ cm^–2 s^–1, on the contrary, discharges of the second type are realized at the beginning. These discharges result in the appearance of channels with inhomogeneities on the glass, at which subsequently discharges of the first type occur. It is determined by calculations that in the region adjacent to the exposed glass surface, secondary electrons accelerated in a field of charge accumulated in the glass make the main contribution to the ionization of gases.     

The Influence of Proton Irradiation on Properties of Glass with ITO Coating

Optics and Spectroscopy - Changes in the surface morphology and optical properties of the samples of K208 glass with an ITO film are studied after the effect of protons with an energy of 20 keV and...     

Changes in K-208 glass transmittance spectra under ionizing radiation and molecular fluxes

The effect of 40-keV electron and proton radiation with a flux density of 5 × 10 cm^?2 s^?1 on the deposition of products of thermostimulated gas release from a polymer composite on a substrate made from protective K-208 glass used for the protection of spacecraft solar panels is experimentally investigated. Analysis of the obtained results shows that, unlike proton radiation, electron radiation results in an increase in the optical density of the glass and stimulates the deposition of gas-release products. It is established that the majority of effects generated as a result of exposure of the substrate to electron radiation are neutralized by protons upon combined irradiation with electrons and protons.     

Reaction of PtCl<Subscript>4</Subscript> with 18-crown-6 in aprotic solvents (Nitromethane,acetonitrile, and 1,2-dichloroethane)

Specific features of the reaction of anhydrous PtCl₄ with 18-crown-6 in anhydrous solvents with different donor and solvating abilities, such as nitromethane, acetonitrile, and 1,2-dichloroethane, under an inert atmosphere are studied. Ionic platinum complexes with oligoethylene glycols or with crown ethers, formed by macroring opening and/or fragmentation under the action of the acidic agent, were isolated. The ¹H NMR, IR, and Raman spectra of the complexes were studied. To assess the coordination mode of the crown ether cleavage product with Pt(IV), quantum-chemical calculations at the density functional theory level were carried out. Original Russian Text E.V. Guseva, R.A. Khasanshin, T.T. Zinkicheva, E.G. Yarkova, V.K. Polovnyak, 2007, published in Zhurnal Obshchei Khimii, 2007, Vol. 77, No. 11, pp. 1805–1815.     

On the Role of the Proton Component in the Evolution of the Morphology of K-208 Glass under Combined Electron–Proton Irradiation

Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques - By the methods of atomic force microscopy (AFM) we investigate the surfaces of samples of K-208 glass after separate...