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31.
The Voronoi–Dirichlet polyhedra (VDP) and the method of intersecting spheres were used to perform crystal-chemical analysis of 106 compounds containing palladium atoms surrounded by halogen atoms. Depending on the oxidation number (2 or 4), Pd atoms can bind 4 to 6 X atoms (X = Cl, Br, I) and form PdX
n
coordination polyhedra shaped like octahedra or square pyramids (n = 6), square pyramids (n = 5), or squares (n = 4). A lone electron pair on Pd(II) was found on the basis of X-ray diffraction data. The influence of the palladium valence state on the key stereochemical features of palladium halide complexes is considered in terms of the 18-electron rule. The tendency of palladium atoms to Pd···H aghostic interactions was noted. 相似文献
32.
Serezhkin V. N. Serezhkina L. B. Shishkina O. V. Pushkin D. V. 《Russian Journal of Coordination Chemistry》2003,29(3):203-218
Using the Voronoi–Dirichlet partition procedure and the method of intersecting spheres, it is demonstrated that in the crystal structures of chalcogen-containing compounds, Pt(IV) atoms form only PtX6 octahedra (X = S, Se, Te), whereas in the case of Pt(III) and Pt(II), square coordination by X atoms is typical. The Pt(II) atoms can also form PtX5 square pyramids (X = S, Se), PtS6 octahedra, and PtTe3Pt3 quasi-octahedra in which a platinum atom is located in the trans-position to each coordinated tellurium atom. It was found that Pt(II) atoms in the PtX4 squares (X = S, Se), unlike square-coordinated Pt(III) atoms, can form one or two Pt–M bonds (M is a d metal) and 1 to 4 secondary Pt–Q bonds, where Q is an s metal or hydrogen. The main features of platinum stereochemistry depending on the metal valence state and coordination number (CN) and on the nature of the chalcogen atom were quantitatively characterized in terms of the Voronoi–Dirichlet polyhedra. 相似文献
33.
The processes going on in silver-doped GeO2 films during air-heating were investigated by XPS, TEM, IR and UV-visible spectroscopy methods. Silver was shown to interact with the GeO2 matrix at 500-600 °C to give silver germanate which was decomposed on further heating to form GeO2 and silver nanoparticles, 10-35 nm in size, absorbing in the plasmon resonance region (λmax = 415 nm). The silver nanoparticles are located deep in the films and encapsulated by oxide particles. 相似文献
34.
Voronoi–Dirichlet polyhedra (VDP) and the method of intersecting spheres were used to perform crystal-chemical analyses of compounds containing complexes [Rh
a
X
n
]
z– (X = F, Cl, Br). It was found that, irrespective of oxidation number (+3, +4, or +5), rhodium atoms always exhibit the coordination number 6 with respect to the halogen atoms and have octahedral coordination. The influence of site symmetry and the valence state of Rh on the distortion of RhX6 octahedra are considered. The electronic configuration of the Rh atoms is shown to influence the symmetry of their valence-force field within the crystal structure. 相似文献
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36.
G. B. Andreev M. Yu. Antipin N. A. Budantseva E. V. Tuchina L. B. Serezhkina A. M. Fedoseev A. B. Yusov 《Russian Journal of Coordination Chemistry》2004,30(12):868-873
A complex of uranyl perchlorate with imidazolidine-2-one as the molecular ligand, [UO2(Imon)4(H2O)](ClO4)2 (I), was synthesized and structurally characterized by X-ray diffraction analysis. The coordination number of the uranium atom is 7. The nearest environment of the uranyl ion includes four O atoms of the imidazolidine-2-one molecules and one O atom of the water molecule. The perchlorate anions are outer-sphere ligands. The crystals are monoclinic: space group P21/c; a = 16.294(3) Å, b = 16.135(3) Å, c = 9.987(2) Å, = 97.69 (3)°, V = 2603.0 (9) Å3, (calcd) = 2.117 g/cm3, Z = 4. The IR and luminescence spectra of the complex were recorded.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 919–924.Original Russian Text Copyright © 2004 by Andreev, Antipin, Budantseva, Tuchina, Serezhkina, Fedoseev, Yusov. 相似文献
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38.
I. V. Medrish E. V. Peresypkina A. V. Virovets L. B. Serezhkina 《Russian Journal of Inorganic Chemistry》2008,53(7):1040-1045
Single crystals of M[UO2(C2O4)(NCS)] · 0.5H2O (M = Rb (I) or Cs (II)) have been synthesized and studied by X-ray diffraction analysis. The compounds are isostructural, and their crystals are monoclinic with the space group C2/c, Z = 4, and unit cell parameters: a = 9.0624(5) Å, b = 13.1242(7) Å, c = 8.9204(5) Å, β = 98.897(2)°, R = 0.0226 (I); a = 9.3171(3) Å, b = 13.2987(5) Å, c = 9.1151(3) Å, β = 101.0860(10)°, R = 0.0214 (II). The main structural units of the crystals of I and II are the [[UO2(C2O4)(NCS)]? chains belonging to the crystal-chemical group AK02M1 (A = UO 2 2+ , K02 = C2O 4 2? , M1 = NCS? of the uranyl complexes. The uranium-containing chains are joined into a three-dimensional framework through electrostatic interactions with the outer-sphere cations and hydrogen bonds involving the water molecules. 相似文献
39.
A. V. Marukhnov D. V. Pushkin E. V. Peresypkina A. V. Virovets L. B. Serezhkina 《Russian Journal of Inorganic Chemistry》2008,53(6):831-836
Compound Na[UO2(SeO3)(HSeO3)] · 4H2O (I) has been synthesized and studied by single-crystal X-ray diffraction. The crystals of I are monoclinic with the unit cell parameters a = 8.8032(5) Å, b = 10.4610(7) Å, c = 13.1312(7) Å, β = 105.054(2)°, space group P21/n, Z = 4, V = 1167.76(12) Å3, R = 0.0394. The main structural units of crystals I are the [UO2(SeO3)(HSeO3)]? layers belonging to the AT3B2 crystal-chemical group (A = UO 2 2+ , T3 = SeO 3 2? , B2 =HSeO 3 ? ) of the uranyl complexes. The sodium ions are linked with oxygen atoms of two uranyl ions of the same layer and with four water molecules. Electroneutral packets that formed are linked into a three-dimensional framework through a system of hydrogen bonds. 相似文献
40.
L. B. Serezhkina A. V. Marukhnov E. V. Peresypkina A. V. Virovets I. V. Medrish D. V. Pushkin 《Russian Journal of Inorganic Chemistry》2008,53(6):837-841
Single crystals of K4[(UO2)2(C2O4)3(NCS)2] · 4H2O(I) have been synthesized and studied by X-ray diffraction. The crystals are monoclinic with the unit cell parameters a = 8.0226(7) Å, b = 14.9493(11) Å, c = 11.1670(9) Å, β = 98.299(3)°, space group P21/n, Z = 2, V = 1325.26(19) Å3, R = 0.0186. The main structural units of the crystals of structure I are discrete binuclear groups [(UO2)2(C2O4)3(NCS)2]4? belonging to the crystal-chemical group A2K02B 2 01 M 2 1 (A =UO 2 2+ , K02 =C2O 4 2? , B01 =C2O 4 2? , M1 = NCS?) of the uranyl complexes. The uranium-containing complexes are linked into a three-dimensional framework through the potassium ions and a system of hydrogen bonds involving the outer-sphere water molecules. 相似文献