Solid Platinum Superoxo Hydroxo Complex

    EPR Spectra Of Green Solid Platinum Superoxo Hydroxo Species

    Solid Platinum Superoxo Hydroxo Complex. Pankratov D.A., Komozin P.N., Kiselev Yu.M. //Russian Journal of Inorganic Chemistry. 2000. V. 45. № 10. P. 1555-1559

    Solid samples isolated from solutions of a platinum superoxo hydroxo complex are studied by EPR and X-ray powder diffraction techniques. The short-lived superoxo complex is found to form upon dissolution of the solid samples in concentrated acids. Magnetic resonance parameters of the platinum superoxo complexes in the solid state and in acidic solutions are determined. The structures of the inner coordination sphere of the found superoxo complexes are discussed.

    Подробнее...

    Печать E-mail

    A Mössbauer study of pentavalent iron in a vanadium(V) oxide matrix

    Mossbauer absorption spectra of iron-doped V2O5.

    A Mössbauer study of pentavalent iron in a vanadium(V) oxide matrix. Dedushenko S.K., Perfiliev Y.D., Tcheboukov D.E., Pankratov D.A., Kiselev Y.M. //Mendeleev Communications. 1999. V. 9. № 5. P. 211-212Search the full text below. Ищи полный текст ниже.

    The formation of iron in the 5+ oxidation state was observed in iron-doped vanadium(V) oxide; this state is characterised by a singlet with the isomer shift δ = -0.56 ± 0.01 mm·s-1 relative to α-iron in the Mössbauer spectrum at room temperature.

    Подробнее...

    Печать E-mail

    Structural Features of Green Cobalt(III) Hydroxide

    Deconvolution of emission Mossbauer spectra for green cobalt(III) hydroxide at 78 K and 298 K according to model 2
    Structural Features of Green Cobalt(III) Hydroxide. D. A. Pankratov, A. A. Veligzhanin, Y. V. Zubavichus //Russian Journal of Inorganic Chemistry, 2013, Vol. 58, No. 1, pp. 67–73Search the full text below. Ищи полный текст ниже.

    Emission Mössbauer and X-ray absorption XANES/EXAFS spectroscopic techniques are applied to elucidate the structural features of green cobalt(III) hydroxide. A comparative analysis of structurally characterized cobalt(II) and cobalt(III) oxo-compounds shows that the parameters of the local environment of cobalt atoms in green cobalt(III) hydroxide differ substantially from those of its analogues.

    According to several reports of the late 50's of the twentieth century, the low-temperature reaction of cobalt(II) chloride with hydrogen peroxide in alcoholic media in the presence of sodium hydroxide affords dark green cobalt(II) peroxide. Although this synthesis protocol is broadly recited (in particular, it is described in all editions of the classical manual on inorganic synthesis by N.G. Klyuchnikov starting from 1965), the formation of such a simple cobalt(II) peroxide compound seems hardly possible. 

    Подробнее...

    Печать E-mail

    Investigation of iron(III) complex with crown-porphyrin

    57Fe complex of 5-(4-(((4-hydroxy-benzo-15-crown-5)-5-yl)diazo)phenyl)-10,15,20-triphenylporphyrin contains iron atoms in two sites, porphyrin and crown-ether rings

    Investigation Of Iron(III) Complex With Crown-Porphyrin. Pankratov D.A., Dolzhenko V.D., Kiselev Y.M., Stukan R.A., Al Ansari Y.F., Savinkina E.V. //Hyperfine Interactions. 2013. V.222. Is.1 (Suppl). P. S1-S11Search the full text below. Ищи полный текст ниже.

    Iron complex of 5-(4-(((4′-hydroxy-benzo-15-crown-5)-5′-yl)diazo)phenyl)-10,15,20-triphenylporphyrin was investigated by 57Fe Mössbauer spectroscopy and EPR. Two Fe sites were identified; they give two differing signals, doublet and wide absorption in a large velocity interval. EPR spectra of solutions of the complex in chloroform at room temperature also show two signals with g = 2.064, AFe = 0.032 cm− 1; g = 2.015, AFe = 0.0034 cm− 1. The doublet asymmetry is studied vs. temperature and normal angle to the sample plane and gamma-beam. The isomer shift δ in the doublet varies from 0.41 to 0.25 mm/s in the 5÷360 K temperature range, whereas quadruple splitting value is constant, Δ ∼ 0.65 mm/s. The relax absorption may be described as a wide singlet (δ = 0.30 ÷ 0.44 mm/s and Γ = 2.83 ÷ 3.38 mm/s); its relative area strongly depends on temperature. According to δ, both signals are assigned to Fe(III).

    Structures and properties of metal porhyrins (MPs) (hemoglobin, chlorophyll, vitamin B12, etc.) participating in vital processes depend on a central metal and peripheral substituents. Most MPs possess chemical and thermal stability, high extinctions coefficients in UV, visible and near IR ranges and reversible red-ox transitions. Therefore, detail study of their properties with the use of various physicochemical methods is of interest.

    Подробнее...

    Печать E-mail

    Electron Paramagnetic Resonance Of Ferrite Nanoparticles

    EPR spectra of Fe2O3 nanoparticles at different temperature. DH is the peak-to-peak linewidth, A is the EPR signal amplitude. It is presumed that S1 is the superparamagnetic signal (g=2.12) from the g-Fe2O3 phase, S2 is the paramagnetic EPR signal (g=2.02) from magnetically isolated centers in g-Fe2O3, S3 is the rhombic symmetry signal (g=4.3) from the a-Fe2O3 phase.

    Electron Paramagnetic Resonance Of Ferrite Nanoparticles. Koksharov Yu.A., Pankratov D.A., Gubin S.P., Kosobudsky I.D., Beltran M., Khodorkovsky Y., Tishin A.M. //Journal of Applied Physics. 2001. V. 89. № 4. P. 2293-2298Search the full text below. Ищи полный текст ниже.

    Three types of iron-based oxide nanoparticles (weight compositions Fe2O3, BaFe2O4, and BaFe12O19) embedded in a polyethylene matrix are studied using the electron paramagnetic resonance technique. All nanoparticles are found to be multiphase. Thermal variations of electron paramagnetic resonance spectra reveal the presence of two phases in the Fe2O3 nanoparticles. One such phase undergoes an antiferromagnetic-like transition near 6 K. Nanoparticles of BaFe2O4 demonstrate a resonance anomaly near 125 K that could indicate the presence of a magnetic phase. Reduced magnetic anisotropy in BaFe12O19 nanoparticles may be related to either structural imperfection or particle smallness (effective diameter of less than 10 nm). Our data clearly show that low temperature experiments are desirable for the correct identification of nanoparticles by means of the elecstron paramagnetic resonance technique.

    Подробнее...

    Печать E-mail

    Яндекс.Метрика

    Top.Mail.Ru
    Top.Mail.Ru

    http://www.youtube.com/RuRedOx

    Feedback | Контакт
    E-mail:
    Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.