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Two cobalt hexammine-vanadate ion-pair complexes have been prepared; one in acid medium (pH≈4) and the other in alkaline medium (pH≈10). The formed complexes were characterized by their elemental analysis, IR and XRD techniques. The complexes were subjected to thermogravimetric and differential thermal analyses. The IR study suggests that the formed complexes were of the ion-pair type, while that of the thermally decomposed compounds revealed the resolution of the originally present broad V=O and V-O-V bands. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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1 INTRODUCTION Palladium (Ⅱ) coordination and organometallic compounds usually show square planar environments at the metal center[1], and have experienced an im- portant development in the past years due to their acting as intermediates in different types of catalytic reactions and numerous applications in organic synthesis[2]. Although palladium plays an increase- ingly recognized role as a biometal[3], little is known about the structure and function of palladium compounds in living …  相似文献   

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Synthesis and Crystal Structure of Na10[P4(NH)6N4](NH2)6(NH3)0.5 with an Adamantane-like Anion [P4(NH)6N4]4? Crystals of Na10[P4(NH)6N4](NH2)6(NH3)0.5 were obtained by the reaction of P3N5 with NaNH2 (molar ratio 1:20) within 5 d at 600°C in autoclaves. The following data characterize X-ray investigations: Fm3 m, Z = 8, a = 15.423(2) Å, Z(F) = 261 with F ≥ 3 σ(F) Z(Variables) = 27, R/Rw = 0.086/0.089 The compound contains the hitherto unknown anion [P4(NH)6N4]4?, which resembles adamantane. The total structure can be described as follows: The centers of gravity of units of [Na8(NH2)6(NH3)]2+ – 8Na+ on the corners of a cube, 6NH2? on the ones of an inscribed octahedron with NH3 in the center – follow the motif of a cubic-closest packed arrangement. Units of [Na12(NH2)6]6+ – 12Na+ on the corners of a cuboctahedron and 6NH2? on the ones of an inscribed octahedron – occupy all octahedral and those of [P4(NH)6N4]4? all tetrahedral sites.  相似文献   

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Synthesis and Crystal Structures of [P(C6H5)4][1-(NH3)B10H9] and Cs[(NH3)B12H11] · 2CH3OH The reduction of [1-(NO2)B10H9]2? with aluminum in alkaline solution yields [1-(NH3)B10H9]? and by treatment of [B12H12]2? with hydroxylamine-O-sulfonic acid [(NH3)B12H11]? is formed. The crystal structures of [P(C6H5)4][1-(NH3)B10H9] (triclinic, space group P1 , a = 7.491(2), b = 13.341(2), c = 14.235(1) Å, α = 68.127(9), β = 81.85(2), γ = 86.860(3)°, Z = 2) and Cs[(NH3)B12H11] · 2CH3OH (monoclinic, space group P21/n, a = 14.570(2), b = 7.796(1), c = 15.076(2) Å, β = 111.801(8)°, Z = 4) reveal for both compounds the bonding of an ammine substituent to the cluster anion.  相似文献   

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Thermolysis of the double-metal complex [Co(NH3)6][Cr(C2O4)3] was studied in air at 200, 350, and 500°C and in a hydrogen atmosphere at 200, 350, 500, 700, and 900°C, as well as the composition and properties of thermolysis products. Oxidative thermolysis produces mixed oxides CoCr2O4 and Co2CrO4; reductive thermolysis produces Co + Cr2O3 mixture. Specific surface areas were measured for reductive thermolysis products; the maximal specific surface area and, therefore, maximal dispersion are reached at 500°C. The morphology of the reductive thermolysis products and the thermolysis chemism were studied in relation to the nature of the complex anion.  相似文献   

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Structural determinations of the magnesium(II) and barium(II) salts of pyromellitic acid (benzene‐1,2,4,5‐tetra­carboxyl­ic acid) are presented. Hexa­aqua­magnesium(II) benzene‐1,2,4,5‐tetra­carboxyl­ate(2−), [Mg(H2O)6](C10H4O8), (I), and penta­aqua­[benzene‐1,2,4,5‐tetra­carboxyl­ato(2−)]­barium(II), [Ba(C10H4O8)(H2O)5], (II), are both centrosymmetric and both possess a 1:1 metal–ligand ratio, but the two structures are found to differ in that the magnesium salt contains a hexaaqua cation and possesses only hydrogen‐bonding interactions between cations and anions, while the barium salt exhibits coordination of the carboxyl­ate ligand to the nine‐coordinate metal centre. In (I), both ions sit on a 2/m site symmetry, and in (II), the cation and anion are located on m and i site symmetries, respectively.  相似文献   

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Binary intercluster compounds (IC) can be reduced to basic structure types of ionic solids. We examined the validity of this concept for ternary compounds, on the example of a quasi-ternary intercluster compound made from a Keggin anion ([PMo12O40]3?), an organic cation (o-xylylenebis(triphenylphosphonium)), and a complex (cobaltocenium). The new compound and its two related quasi-binary IC were investigated by X-ray diffractometry, examined for intermolecular interactions such as hydrogen-bonding, π–, or van der Waals-interactions, and evaluated for possible reductions to basic structure types.  相似文献   

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A structure of the [P(C6H5)4][MnFe(C2O4)3] single crystal is studied by X-ray diffraction within the 100–370 K temperature interval. The phase transition observed in the 150–170 K region is probably due to the cooperative ordering of the axial phenyl rings of the organic cations in the special positions.  相似文献   

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[CH3NH3][NH3(CH2)6NH3]H3[P2Mo2W16O62]·H2O的水热合成与表征   总被引:4,自引:0,他引:4  
首次合成了[CH3NH3][NH3(CH2)6NH3]H3[P2Mo2W16O62]·H2O,通过元素分析、红外光谱和X射线单晶衍射对合成产物进行了表征,并用TGA-DSC研究了化合物的热稳定性.晶体属单斜晶系,P21/m空间群,a=1.2596(3)nm,b=1.8715(4)nm,c=1.9816(4)nm,α=γ=90°,β=90.16(3)°,V=4.671(2)nm3,Z=2,Mr=4358.66,Dc=3.100g·cm-3,μ=19.978mm-1,F(000)=3792,R=0.0835,Rw=0.2026.结果表明,在晶体结构内形成了0.7364nm×0.8354nm的微孔.  相似文献   

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