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Information × Registration Number 0217U007469, 0116U002521 , R & D reports Title Polyoxomolybdates and polyoxotungstates with single, double, and triple charged metal cations for the development of new materials popup.stage_title Head Rozantsev Georgii M., Доктор хімічних наук Registration Date 15-01-2018 Organization Donetsk State University popup.description2 The conditions for the direct synthesis of 14 new lanthanide heteropoly hexatungstonickelates(II) Ln4[Ni(OH)6W6O18]3?nH2O (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) from the Ni2+-WO42--H+-H2O (n(Ni2+):n(WO42-):n(H+)=1:6:6) solutions were elaborated. Using FTIR spectroscopy it was shown that FTIR spectra for all lanthanide salts follow a common pattern in the Tungsten-Oxygen framework (400-1000 cm-1) and heteropoly anion [Ni(OH)6W6O18]4- contained in the isolated salts has an Anderson-type structure. It was found out that the position of the absorption band corresponding to stretching vibrations of the W=O bond for a number of Ln4[Ni(OH)6W6O18]3·nH2O salts remains practically unchanged (949-952 cm-1). At the same time, the position of the absorption bands of stretching vibrations in W-O-W bridge fragments in the 660-673 cm-1 and 876-886 cm-1 regions varies more and practically linearly depends on the ordinal number of the lanthanide. It was shown that on the dependences of the absorption bands at 470-488 cm-1 vs. values of multiplicity (S) and angular moments (J) the pronounced "Gadolinium break" and "double-double effect" are observed due to the spin-spin interactions. The spin-orbital interactions are apparent as tetrad effect on the dependences of the same absorption bands vs. values of orbital (L) moments. The conditions for the synthesis of novel dysprosium (III)-containing salt with heteropoly tungstate anion were determined. By the methods of chemical analysis and FTIR spectroscopy it was shown that sodium heteropoly decatungstatedysprosiate(III) Na9[Dy(W5O18)2]·30H2O was precipitated from Na2WO4 solution under Z=?(H+)/?(WO42-)=0,80 after adding of acetone. An X-ray single crystal analysis was carried out and model of crystal structure for Na9[Dy(W5O18)2]·30H2O (a = 12.966(3)A, b=12.977(3)A, c=40.772(3)A, a=82.78(3)°, b=83.08(3)°, y=77.22(3)°, V=6606.9(4) A3, Z=4, triclinic crystal system, space group P1) was obtained. Interaction in the solutions of Sm(NO3)3-Na2WO4-HNO3-H2O system in the range of acidity Z from 0.80 to 1.20 range was studied; the data confirming possible formation of three previously undescribed salts with heteropoly decatungstatesamarate (III)-anion - Na9[Sm(W5O18)2]·30H2O (Z = 0.80), Na7H2[Sm(W5O18)2]·24H2O (Z = 0.90) and Na5Н4[Sm(W5O18)2]·17H2O (Z = 1.00), as well as one salt with paratungstate B anion Sm10[W12O40(OH)2]3·104H2O was obtained. Substitution rare-earth elements for cadmium in the monoclinic compounds Ln2MoO6 (Ln - Gd, Ho) leads to the formation of fluorite-related cubic structure. Series Ln2-xCdxMoO6-x/2 was investigated by XRD (with structure refinement), scanning electron microscopy, FTIR-spectroscopy and conductivity measurements. Product Description popup.authors Єрошина Катерина Вікторівна Іванцова Елла Сергіївна Арзамасцева Тетяна Олександрівна Баумер Вячеслав Миколайович Борисова Катерина Володимирівна Гетьман Євген Іванович Гумерова Надія Ісмагілівна Марійчак Олександра Юріївна Радіо Сергій Вікторович Розанцев Георгій Михайлович Румянцева Жанна Олександрівна Усачов Олег Михайлович popup.nrat_date 2020-04-02 Close