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1.
A.A Bessonov A.M FedosseevJ.-C Krupa I.B ShirokovaN.A Budantseva 《Journal of solid state chemistry》2002,169(2):182-188
A new method of synthesis of oxide tungsten bronzes containing lanthanide (Ln) Nd and Eu, based on thermal degradation of polyoxotungstate compounds, is proposed. The simplicity of the method allows to consider this class of compounds with chemical formula, LnxWO3, as potential inert target for incineration or transmutation of minor actinides, Am and Cm, in neutron reactors. Nd and Eu were used as analogues of transplutonium elements. Powder X-ray diffraction patterns of compounds synthesized reveal a cubic perovskite structure. The lanthanide content in bronzes was determined by optical spectroscopy analysis. The experimental density of the pressed bronze samples was estimated at 6.58 g cm−3, i.e., 89% of the crystallographic value. The thermal stability of the bronzes synthesized was checked up to 900°C in an inert atmosphere. Leaching tests were performed for europium bronzes in nitric acid solutions using luminescence technique. 相似文献
2.
Fedoseev A. M. Budantseva N. A. Andreev G. B. Yusov A. B. Shirokova I. B. 《Russian Journal of Coordination Chemistry》2002,28(4):279-284
The reactions of some rare-earth elements (La, Ce, Sm, Lu, Gd) and Am(III) with heteropolymolybdate anions are studied. The complexation rate constants of Am(III) in a solution with Al(OH)6Mo6O18
3- and Cr(OH)6MoO18
3-
6 (1 = 18 ± 6 and 25 ± 5, respectively) are determined by spectral methods. The Ln[Al(OH)6Mo6O18] · nH2O, Eu[Cr(OH)6Mo6O18] · nH2O, and Am[Al(OH)6Mo6O18] · nH2O isostructural compounds are synthesized. The crystal structure of the Sm[Al(OH)6Mo6O18] · 11H2O complex was determined by the X-ray diffraction analysis. The results of spectroscopic and thermogravimetric studies of the obtained compounds are presented. 相似文献
3.
Budantseva N. A. Andreev G. B. Krot N. N. Antipin M. Yu. 《Russian Journal of Coordination Chemistry》2003,29(3):222-226
X-ray diffraction and spectroscopic data for a new Np(V) compound, namely, [NpO2{OC(NH2)2}5](NO3) (I) are presented. Crystals are monoclinic, space group P21, a = 11.142(2) Å, b = 7.6379(9) Å, c = 11.143(2) Å, = 108.9(1)°, Z = 2, V = 897.1(2) Å3. The neptunium atom has a typical pentagonal-bipyramidal environment with five oxygen atoms of the carbamide molecules in the equatorial plane. The nitrate ion is in the outer sphere. Carbamide is a strong molecular ligand with respect to Np(V) and hence, cation–cation bonds of the NpO2
+ ions are not realized in structure I. The wave length of the f–f transition in the electronic absorption spectra of crystalline complex I and Np(V) in a saturated carbamide solution is virtually the same and is equal to 991 nm. 相似文献
4.
M. N. Sokolova N. A. Budantseva A. M. Fedoseev 《Russian Journal of Coordination Chemistry》2011,37(6):478-482
The U(VI) complex with cyanoacetic acid, [UO2(H2O)2(NCCH2COO)2] (I), was synthesized from an aqueous solution, and its X-ray diffraction analysis was carried out. The crystals are orthorhombic: space group Pca2 1, a = 25.9605(7) Å, b = 6.7634(2) Å, c = 6.3398(2) Å, V = 1113.15(6) Å3 at 100 K, and Z = 4. The coordination polyhedron of the uranium atom is a distorted pentagonal bipyramid. The cations UO 2 2+ are bound into infinite zigzag chains by the bridging carboxyl groups of one of the anions of cyanoacetic acid. The carboxyl oxygen atom of the second anion, which is not involved in coordination, and the nitrogen atoms of the cyano groups form hydrogen bonds with the coordination water molecules. The layer structure of the compound is formed through the hydrogen bonds. The absorption spectra in the visible and infrared ranges of the crystalline compound are measured and analyzed. 相似文献
5.
N. A. Budantseva G. B. Andreev A. M. Fedoseev M. Yu. Antipin J.-C. Krupa 《Crystallography Reports》2003,48(1):58-60
The crystal structure of the [NpO2(NO3)(Terpy)(H2O)] complex between pentavalent neptunium and 2,2′,6′,2″-terpyridine is determined. The crystal data are as follows: a = 11.130(3) Å, b = 7.916(2) Å, c = 18.324(5) Å, β = 100.873(6)°, V = 1585.5(8) Å3, Z = 4, space group is P21/n, R = 0.044, and wR(F 2) = 0.092. The coordination polyhedron of the Np atom is a pentagonal bipyramid whose equatorial plane includes three nitrogen atoms of the Terpy molecule and two oxygen atoms of the nitrate ion and the water molecule. 相似文献
6.
M. S. Grigorev A. M. Fedoseev N. A. Budantseva A. A. Bessonov J. -C. Krupa 《Crystallography Reports》2004,49(4):598-602
The crystal structure of the K2[(NpO2)2(CrO4)3(H2O)] · 3H2O compound was established. The structure consists of anionic layers [(NpO2)2(CrO4)3(H2O)]
n
2n
, between which K+ ions and crystallization water molecules are located. The coordination polyhedra of Np atoms are distorted
pentagonal bipyramids. All chromate ions are bound in a tridentate-bridging fashion.
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Translated from Kristallografiya, Vol. 49, No. 4, 2004, pp. 676–680.
Original Russian Text Copyright ? 2004 by Grigor’ev, Fedoseev, Budantseva, Bessonov, Krupa. 相似文献
7.
G. B. Andreev M. Yu. Antipin N. A. Budantseva N. N. Krot 《Russian Journal of Coordination Chemistry》2005,31(11):800-803
A new neptunium(V) complex [(NpO2)2(CH3COO)2(H2O)] ? 2H2O was synthesized and its crystal structure was determined. The unit cell parameters are: a = 24.007(10) Å, b = 6.779(3) Å, c = 8.076(3) Å, space group Pnma, Z = 4, V = 1314.2(9) Å3, R = 0.049, wR(F2) = 0.105. The crystal structure of the compound is composed of neutral [(NpO2)2(CH3COO)2(H2O)] layers and molecules of the water of crystallization. Each of the crystallographically independent neptunoyl ions performs a bidentate function thus forming a composite system of cation-cation bonds. 相似文献
8.
9.
N. A. Budantseva G. B. Andreev A. M. Fedoseev L. N. Astafurova M. Yu. Antipin 《Russian Journal of Coordination Chemistry》2005,31(11):804-808
A new neptunium(VI) complex [(NpO2)(CrO4)(H2O)] ⋅ 4H2O (I) was synthesized, its crystal structure was determined, and the IR and near-IR absorption spectra were measured. The unit
cell parameters are: a = 8.634(4) Å, b = 11.119(4) Å, c = 9.410(3) Å, β = 92.40(3)°, space group P21/c, Z = 4, V = 902.6(6) Å3, R = 0.048, wR(F
2) = 0.054. The crystal structure of the compound is composed of the [(NpO2)(CrO4)(H2O)]
n
layers and the crystal water molecules located between the layers. The coordination polyhedron of neptunium is a pentagonal
bipyramid whose equatorial plane is formed by the oxygen atoms of two bridging water molecules and three chromate ions. The
Np(VI) complexation with the chromate ions in an aqueous solution at μ = 1 was studied by spectrophotometry. The stability
constants for 1 : 1 and 1 : 2 complexes were calculated, logβ1 = 3.19(2), logβ2 = 3.93(2), respectively.
__________
Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 11, 2005, pp. 848–852.
Original Russian Text Copyright ? 2005 by Budantseva, Andreev, Fedoseev, Astafurova, Antipin. 相似文献
10.
Grigor'ev M. S. Fedoseev A. M. Budantseva N. A. 《Russian Journal of Coordination Chemistry》2003,29(12):877-879
The crystal structure of the mixed-valence Np(V) and Np(VI) compound Na6[(NpVO2)2(NpVIO2)(MoO4)5] · 13H2O was determined. The structure is built of the anionic layers [(NpVO2)2(NpVIO2)(MoO4)5]
6n-
n with the Na+ cations and crystal water molecules between them. The Np(V) and Np(VI) atoms in the anionic layers are ordered. The motif of the anionic layer is close to that found in Mg2[(UO2)3(SeO4)5] · 16H2O. The isostructural mixed-valence Np(V) and U(VI) compound was also synthesized. 相似文献