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41.
An integrated Xray diffraction study was performed on polycrystals and single crystals of three new isostructural phases with general formula Ag4A2[M(NO2)4]3 (M = Pd, Pt; A = K, Rb). Data on the crystal structure solution (CAD4 diffractometer, MoK radiation, graphite monochromator = 2–30° are presented. In one crystallographically independent [M(NO2)4]2- complex anion, the planar square coordination of the central atom is completed to 4 + 2 by two oxygen atoms at a distance of 3.02–3.12 in the other anion, it is completed to 4 + 1 + 1 by an oxygen atom at a distance of 3.12–3.30 and an Ag+ cation at a distance of 3.04–3.11 . Part of the Ag+ cations form Ag - Ag dimers with a distance of 3.03–3.07. Crystalchemical analysis of known structures containing [Pd(NO2)4]2- complex anions was performed. It has been established that in none of the cases do any of the possible limiting configurations occur.  相似文献   
42.
The structures of two isostructural phases of [M(Еn)3](ReO4)2 (M = Ni, Zn; Еn is ethylenediamine) are studied. The crystal structures belong to the triclinic system, but demonstrate a pseudohexagonal packing motif. It is shown that the product of thermal decomposition of [Zn(Еn)3](ReO4)2 (hydrogen atmosphere, 400 °C) is a homogeneous mixture of nanocrystalline zinc and rhenium powders with coherent scattering regions of ~30 nm.  相似文献   
43.
Reactions of nitrite complexes of Pd, Ru, and Rh with sulfamic acid were studied by the 14, 15N, and 17O NMR method. Chemical shifts were assigned, and the predominant forms of the complexes were established. The reaction products at room temperature are cis-nitroaqua complexes. Coordination of the sulfamate ion upon storage for a long time or on heating was detected.  相似文献   
44.
A new Pd nitrate complex KCs[Pd(NO3)4]·0.5H2O is synthetized. Its crystal structure contains isolated complex anions [Pd(NO3)4]2−, cations K+, Cs+, and crystallization water. Square-planar coordination around Pd is achieved by oxygen atoms of monodentate nitrate ligands. The coordinated nitrate ligands are all oriented in the same way, in a “basket”-like arrangement. The coordination around Pd is completed to 4+1 by forming Pd...Pd contacts of 3.564 ?. Original Russian Text Copyright ? 2009 by S. P. Khranenko, I. A. Baidina, N. V. Kuratieva, and S. A. Gromilov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 1, pp. 173–176, January–February, 2009.  相似文献   
45.
The crystal structure of [Ni(en)3](ReO4)2 (en is ethylenediamine) is studied: a = 8.3997(2)?, b = 15.6167(5)?, c = 14.2406(4)?, β = 100.378(1)°, V = 1837.46(9) OA3, P21/c space group, Z = 4, and d x = 2.673 g/cm3. It is shown that packing of the complex cations can be considered as single-layer pseudohexagonal. Thermal decomposition of the salt in a hydrogen atmosphere at 550°C is used to obtain a mixture of nickel with a nanocrystalline Re0.87Ni0.13 solid solution (a = 2.733(2)?, c = 4.400(3)?, P63/mmc space group; CSR size is ∼14 nm).  相似文献   
46.
The crystal structure of [Cu(En)2CrO4]n (En is ethylenediamine) is determined: a = 14.7359(4) Å, b = 9.8083(3) Å, c = 14.2664(4) Å, V = 2061.98(10) Å3, space group Cmce, Z = 8, dx = 1.931 g/cm3. It is demonstrated that the studied phase is isostructural with [Сu(Еn)2SO4]n. A pseudotetragonal copper atom coordination (Cu–N 2.0204 Å and 2.0244 Å, ∠N–Cu–N 84.73°) is completed to distorted octahedral by two oxygen atoms of chromate anions (Cu–O 2.433 Å and 2.380 Å).  相似文献   
47.
Crystal structure of a complex salt [CoEn3]2(W7O24)·6H2O is determined by X-ray crystallography. Powder X-ray diffraction is applied for the phase identification of the products of thermal decomposition of the salt in the helium atmosphere.  相似文献   
48.
Nitric acid solutions (c Pd up to 3.2 M) with variable HNO3 concentration were studied by electronic spectroscopy, 14N and 17O NMR, acid-base titration, gravimetry, and other methods. Solid phases that precipitated on storing these solutions were studied by X-ray phase analysis, thermogravimetry, and IR spectroscopy. The conditions for stability of particular Pd(II) species were determined, and specific features of aging of such highly concentrated palladium solutions were revealed. A procedure for palladium isolation as [Pd(NH3)4](NO3)2 from nitric acid solutions in 98% yield was developed.  相似文献   
49.
The paper describes the preparation techniques for β-fac-[Rh(NO2)3(NH3)3]. The complex crystallizes as colorless prisms belonging to the monoclinic crystal system. Crystal data: a = 6.6338(2) Å, b = 11.0627(3) Å, c = 11.5314(3) Å; β = 96.608(1)°, V = 840.64(4) Å3, space group P21/n, Z = 4, dcalc = 2.308 g/cm3. The structure is molecular and contains neutral complex molecules having the fac configuration. Crystal chemical analysis of the complex in comparison to α-fac-[Rh(NO2)3(NH3)3] is performed.  相似文献   
50.
Crystal structures of [Co(NH3)5Cl]MoO4 and [Co(NH3)5Cl]WO4 complex salts are determined by single crystal X-ray diffraction. It is demonstrated for both salts that within the temperature range T = ?123?20°C there is a negative thermal expansion (about 0.26%) towards the c axis of the orthorhombic unit cell (Pnma space group). Thermal properties of the salts are investigated. The phase composition of the products obtained on heating the salts in different gas atmospheres is studied.  相似文献   
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