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21.
The crystal structures of [CuL](NO3)(ReO4) and [CuL](ReO4)2 (L is 4,6,6-trimethyl-1,9-diamino-3,7-diazanon-3-en) are studied. The square coordination of the copper atom in [CuL](NO3)(ReO4) is completed to a distorted octahedron by two oxygen atoms: Cu…O (ReO 4 ? ) 2.393 Å and Cu…O (NO 3 ? ) 2.685 Å, and that in [CuL](ReO4)2, by Cu…O(ReO 4 ? ) 2.468 Å and 2.697 Å. The products of thermolysis of the salts in a hydrogen atmosphere at 800°C are mixtures of nanocrystalline metal powders with coherent scattering regions of ~45 nm.  相似文献   
22.
At T = 150 K, the crystal structure of [Cu(NH3)4](ReO4)2 is studied: a = 6.5167(3) ?, b = 6.7790(3) ?, c = 7.4627(3) ?, α = 67.336(1)°, β = 80.004(1)°, γ = 70.687(1)°, V = 286.70(2) ?3, P-1 space group, Z = 1, d x = 3.661 g/cm3. We analyze the packing of ions using the translation sublattice isolation technique.  相似文献   
23.
Mixed salts of noble metals with the general formula [Pd(NH3)4][MA6], where M = Re, Os, Ir, Pt;A = Cl,Br, and Ag2[Pd(NO2)4]-Ag1-xNaxNO2 (x> 0.3) have been synthesized and studied by X-ray diffractometry. It was found that the former are isostructural to each other and the latter are isostructural to Na2[Pd(NO2)4j-NaNO2. The structural motif of these compounds was established and metal-metal distances were estimated by the cation sublattice method In all cases, metal atoms form common cation sublattices with lattice parameters between 4.5 and 6.3 Å. An original approach to revealing common sublattices in crystal structures where the fragments differ considerably in weight is described.  相似文献   
24.
The reaction products of palladium(II) nitration with sodium nitrite in the presence of rubidium salts are described. The crystal structure of rubidium dinitrodichloropalladoate(II) — trans-Rb2[Pd(NO2)2Cl2] — has been studied (KUMA automatic diffractometer, MoK radiation, graphite monochromator, /2 scan mode for 2 < 30°, 758 experimental reflections, R = 0.030; R = 0.023 for I>2(I)). Crystal data: a = 15.123(3), b = 7.750(2), c = 7.776(2) , V = 911.4(4) 3, space group Cmca, Z = 4, d calc = 3.209 g/cm3. The structure consists of [Pd(NO2)2Cl2]2– complex anions and Rb+ cations. The planar square coordination of the Pd atom is completed to distorted octahedral by the chlorine atoms of the neighboring complexes at Pd...Cl distances of 3.18 . Chains of complexes with alternating orientations are formed. The geometrical characteristics of the complex anions, the coordination polyhedra of the cations, and the heavy atom sublattice are analyzed. The crystal structure of Na2[Pd(NO2)4] has been refined, and refinement data are given.  相似文献   
25.
The monoclinic modification of [Cu(NH3)4](ReO4)2 complex salt in the range 100-410 K is studied by single crystal X-ray diffraction. The crystallographic data for 300 K are as follows: a = 10.6123(3) Å, b = 7.5443(2) Å, c = 15.2261(4) Å, β = 108.406(1)°, V = 1156.67(5) Å3, space group Р21/n, Z = 4, dx = 3.623 g/cm3. The coordination environment of the Cu atom, being a distorted square formed by four nitrogen atoms with Cu–N of 1.997-2.018 Å, is completed by the contacts with two oxygen atoms Cu…O of 2.472 Å and 2.598 Å. The comparative crystal chemical analysis with the triclinic modification of [Cu(NH3)4](ReO4)2 known in the literature is performed.  相似文献   
26.
Four complex salts with the polyatomic [Rh(NH3)6]3+ cation are synthesized and studied by X-ray diffraction. The crystallographic characteristics of [Rh(NH3)6](WO4)Cl are determined and the structures of [Rh(NH3)6]Cl3, [Rh(NH3)6](ReO4)3·2H2O, and [Rh(NH3)6](MoO4)Cl·3H2O are solved. The features of mutual packing of the fragments are studied.  相似文献   
27.
The complex study of barium metaborate crystals has been undertaken with the aim to determine the conditions of their growth with the minimum density of inclusions. It is shown that almost all the inclusions are multiphase formations of the melt type, and, in addition to the mixture of the main components of the quasieutectic composition, they can also be enriched with gas-forming impurities not removed during barium metaborate synthesis. It is shown that the amount and the composition of melt-like inclusions in crystals depends on the removal of by-products of the reactions used for barium metaborate synthesis from the system, the patterns of the convective flows in the flux, the character of its flow under the interface, the axial temperature gradient in the solution, and the temperature fluctuations at the crystallization front.  相似文献   
28.
29.
The structure of double complex salts [Pd(NH3)3(NO2)][Rh(NH3)2(NO2)4] and [PdEn2][Rh(NH3)(NO2)5]·0.75H2O is determined by single crystal X-ray diffraction. In the structures, the main structural moieties are identified.  相似文献   
30.
At T = 150 K the crystal structure of [Cu(en)2] (ReO4)2 (en is ethylenediamine) is studied: a = 6.6229(1) ?, b = 14.2968(3) ?, c = 7.4859(2) ?, β = 102.415(1)°, V = 692.24(3) ?,3, P21/c space group, Z = 2, d x = 3.282 g/cm3. Packing of complex cations is shown to be single layered and pseudohexagonal. Perrhenate anions are located between these layers and additionally coordinate copper atoms with Cu...O distances being 2.504(3) ?.  相似文献   
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