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41.
Single crystals of trans-[Pd(NO3)2(H2O)2] were obtained, and the crystal structure of this complex, previously obtained for polycrystals, was refined. Crystal data (BRUKER X8APEX diffractometer): a = 4.9973(7) Å, b = 10.5982(14) Å, c = 11.7008(17) Å, V = 619.70(15) Å3, space group Pbca, Z = 4, d calc = 2.856 g/cm3. The structure is composed of neutral complexes with a trans configuration. The square plane environment of the Pd atom is formed by four oxygen atoms (Pd-O(NO3) 1.999(5) Å, Pd-O(H2O) 2.030(5) Å) and completed to a distorted bipyramid by two intramolecular contacts (Pd…O(NO3) 2.926 Å). The shortest hydrogen bonds are O…H 2.72 Å.  相似文献   
42.
The crystal structure of Na[Rh(acac)2Cl2] · H2O (acac) =C 5H7O 2 ? )is determined The crystals are triclinic, space group P1, with unit cell dimensions a =12.616(2), b =8.411(4), c =8.499(4) å,a =108.37(4), Β =95.47(4), γ =110.45(4)?, V =780.3(6) å 3, Z =2, d calc =1.758 g/cm 3, R =0.0461. The strong pseudoperiodicity observed experimentally (no reflections with odd indices h) led to a set of experimental data obtained in the unit cell that is reduced along the a axis (“Syntex P2 1 ” automatic diffractometer, λMoK α, graphite monochromator), 1466 measured and 1302 observed Ihkl included in the calculation. This is due to the alternation of the central atoms of octahedral complex onions at intervals of 1/2a. The Rh- 0 and Rh- Cl distances are, on the average, 2.001(3) and 2.325(2), respectively. The cis- angles of ClRhO type are close to 90?, and the average value of the ORhO chelate angle is 95.1? (within 3Σ with Σ ? 0.1?). The average interatomic distances and bond angles (according to types) in the acac ligand are as follows: O- C 1.274, (C- C)ring 1.397, Cring- Csub 1.506 å with Σ not higher than 0.006 å,RhOC 122.2?, (OCC) ring 126.4?, (OCC)term 114.2?, (CCC)ring 127.3?, (CC)ringcsub 119.3? (Σ within 0.2– 0.6?). The distorted octahedron around the Na ion consists of five O atoms (of the H2O molecule and the neighboring acac ligands, distances within 2.364– 2.409 å) and one Cl ion lying at a distance of 2.970 å. The structure in general is of ribbon type: Rh1,2 and Na octahedra are linked by a common edge O(2′)O(1) and common face O(3)O(4′)O(2′) into infinite ribbons, which are extended along the [100] axis and which are translationally identical in the [010] and [001] directions. The H 2O molecule forms two Cl(l)...H2O...Cl(2′) hydrogen bonds: 3.116 and 3.179 å, respectively, which link the Rh octahedra into infinite chains in the [120] direction.  相似文献   
43.
Single crystal X-ray diffraction was applied for re-determination of the crystal structure of α-trans-[Pd(NH3)2Cl2]. It has been demonstrated that, in contrast to the literature data, the structure is disordered. This model does not require excess over-stoichiometric palladium. Two crystals obtained in the same experiment illustrate possible variations in the packing of the molecules of the complex.  相似文献   
44.
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   
45.
By single crystal X-ray diffraction the crystal structure of the complex salt [Co(NH3)5Cl]2(W10O32)·4H2O is determined and the IR spectrum is interpreted. The crystal chemical analysis of the structure of complex cations and decatungstate anions and their packing in the structure is performed.  相似文献   
46.
Single crystals of a new modification of the di(nitrato)di(aqua)palladium(II) complex β-trans-[Pd(NO3)2(H2O)2] were obtained. Their crystal structure was determined: monoclinic crystal system, a = 5.7469(4) Å, b = 5.3942(6) Å, c = 10.0956(10) Å, β = 97.401(3)°, P21/c, Z = 2, d calc = 2.851 g/cm3, Bruker X8 APEX CCD, MoK α , 836 independent reflections, room temperature. The square-plane coordination of the Pd atom is formed by four oxygen atoms (Pd-O(NO3) 2.003(3) Å and Pd-O(H2O) 2.021(4) Å) and completed to a distorted bipyramid by two intramolecular contacts (Pd…O(NO3) 2.893 Å). A comparative crystal-chemical analysis with α-trans-[Pd(NO3)2(H2O)2] was carried out.  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.
Complexation between crystalline trans-[Pd(H2O)2(NO3)2] and acetylacetone was studied. The complexes Pd2(Acac)2(μ-NO3)2(I) and Pd2(Acac)2(μ-Acac)(μ-NO3)(II) were obtained and examined by elemental analysis, X-ray powder diffraction analysis, differential scanning calorimetry, simultaneous thermal analysis, mass spectrometry, and vibrational spectroscopy.  相似文献   
49.
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   
50.
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   
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