Platinum(IV) Superoxo Complexes

Platinum(IV) Superoxo Complexes. Kiselev Yu.M., Pankratov D.A., Ezerskaya N.A., Kiseleva I.N., Shundrin L.A., Popovich M.P. //Russian Journal of Inorganic Chemistry. 1994. V.39. №8. P. 1278-1283

The products of reaction of platinum(IV) hydroxo complexes with ozone in alkaline solutions were studied using various physicochemical methods: electronic spectroscopy, electron spin resonance, and cyclic voltammetry. The arguments presented suggest that the blue solutions obtained contain superoxo Pt(IV) complexes.

One of the most efficient ways to stabilize higher oxidation states in the transition elements is complex formation in aqueous-alkaline media. In this case, hydroxyl ions offer advantages over other ligands and produce a stronger decrease in E° of a redox system than other, rather weakly polarizable ligands, which form complex ions in acid and neutral media. This circum stance is the one favoring stabilization of the highest oxidation states in neptunium, plutonium, americium(VII), and iron(VIII).

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Vibrational Spectra of Platinum Superoxo Complexes

Vibrational spectra of platinum superoxo complexes. Pankratov D.A., Kiselev Yu.M., Sokolov V.B. //Russian Journal of Inorganic Chemistry. 2000. V. 45. № 9. P. 1388-1393

Aqueous alkaline (KOH, KOD) solutions of hexahydroxoplatinate and "blue" superoxohydroxo-platinate complexes were studied by Raman spectroscopy. The spectra of superoxo complexes shows the bands at 1020 and 1060 cm^-1 that arise from the O₂^- moiety. Solid samples of platinum hydroxide and the precipitates isolated from "blue" solutions were studied by IR and Raman spectroscopy. The spectra of hexahydroxoplatinate(IV) were assigned assuming the C_3i symmetry of the Pt(OH)₆^2- group. The Raman spectra of the decomposition products of the solid superoxo complex (ν_O-O = 1080 cm^-1 for O₂^-) show the bands that arise from a platinum peroxo complex (ν_O-O = 829 cm^-1 for O₂^2-).

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EPR Spectra Of Solutions Of Platinum Superoxo Hydroxo Complexes

EPR Spectra Of Solutions Of Platinum Superoxo Hydroxo Complexes. Komozin P.N., Pankratov D.A., Kiselev Yu.M. //Russian Journal of Inorganic Chemistry. 1999. V. 44. № 12. P. 1945-1951

EPR spectra of platinum superoxo hydroxo complexes in alkaline solutions were studied at various alkali concentrations. The EPR parameters for new platinum complexes were determined; the g-factors and hyperfine coupling constants were interpreted in terms of the ligand field theory. The structure of the platinum coordination sphere in the superoxo hydroxo complexes is discussed based on the EPR data.

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Chlorination As A Means For Changing The Composition Of Iron-Containing Nanoparticles In A Polyethylene Matrix

Chlorination As A Means For Changing The Composition Of Iron-Containing Nanoparticles In A Polyethylene Matrix, Pankratov D.A., Yurkov G.Yu., Astaf'ev D.A., Gubin S.P. //Russian Journal of Inorganic Chemistry. 2008. Т. 53. № 6. С. 933-942

Mössbauer spectroscopy, X-ray powder diffraction, and transmission electron microscopy were used to study the reactions of Fe₃O₄ or FeCl₂·4H₂O nanoparticles stabilized in a polyethylene (HPPE) matrix with gaseous chlorine and hydrogen chloride. These reactions produce FeCl₂·2H₂O nanoparticles, which retain the particle size and distribution over the HPPE matrix intrinsic to precursor nanoparticles. We propose chemical modification of iron-containing nanomaterials as a means for manufacturing iron(II) chloride nanoparticles.

The synthesis and study of various nanomaterials and their properties have recently become a focus of research due to their unique electronic, optical, magnetic, and other physical and chemical properties. The physical and chemical properties of nanomaterials are primarily determined by their chemical composition. Therefore, preparing materials containing nanoparticles of the desired chemical composition is a problem faced by researchers. A considerable number of processes are known to yield metal-containing nanoparticles: chemical, electrochemical, pyrolytic, spark, micellar, and mechanochemical [10]. 

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