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11.
The title complex cis-bis(tetrahydrothiophene)-bis(nitrate) platinum(II), (tht)2Pt(NO3)2, was the reducing product from potassium hexachloroplatinate(IV) K2PtCl6 where the platinum is tetra-valenced. Crystal data for C8H16N2O6PtS2: monoclinic, space group P21/c, a = 9.8833(5), b = 8.6744(4), c = 18.6407(9) (A), β = 114.401(3)°, V = 1455.35(12) (A)3, Z = 4, Mr = 495.44, Dc = 2.261 g/cm3, F(000) = 944, μ = 9.950 mm-1, λ(MoKα) = 0.71073 (A), T = 293(2) K, 2θmax = 54.96o, GOOF = 1.033, R = 0.0350 and wR = 0.0785 for 2572 observed reflections with I > 2σ(I). X-ray diffraction studies reveal that the title complex has interesting weak metal-metal interactions and two molecules linked by metal-metal interaction exist as a group. Luminescent spectrum illuminates red emission of the complex at room temperature.  相似文献   
12.
A novel microporous polyhedral framework [Zn(6)(btb)(4)(4,4'-bipy)(3)(dmf)(55)(H(2)O)(32)] with high surface area has been designed and synthesized, which shows high multigas-uptake capacity via supercritical carbon dioxide (SCD) activation.  相似文献   
13.
The title complex cis-bis(tetrahydrothiophene)-bis(nitrate) platinum(H), (tht)2Pt(NO3)2, was the reducing product from potassium hexachloroplatinate(IV) K2PtC16 where the platinum is tetra-valenced. Crystal data for CsH16N206PtS2: monoclinic, space group P21/c, a = 9.8833(5), b = 8.6744(4), c = 18.6407(9)A,β = 114.401(3)°, V = 1455.35(12)A3 Z = 4, Mr = 495.44, Dc = 2.261 g/cm3, F(000) = 944,μ = 9.950 mm-1, 2(MoKa) = 0.71073 A, T= 293(2) K, 2θmax = 54.96°, GOOF = 1.033, R = 0.0350 and wR = 0.0785 for 2572 observed reflections with I 〉 2σ(I). X-ray diffraction studies reveal that the title complex has interesting weak metal-metal interactions and two molecules linked by metal-metal interaction exist as a group. Luminescent spectrum illuminates red emission of the complex at room temperature.  相似文献   
14.
谢秀兰  曹荣 《结构化学》1994,13(6):480-488
对~(95)MoNMR的特点、提供的信息、发展历史以及研究现状作了较为全面的介绍。结合本实验室研究工作和部分文献报道对其在钼化学研究中的应用进行了较为详细的论述,同时还指出影响~(95)MoNMR的因素并进行了简单分类和讨论。  相似文献   
15.
ZnO and Pd nanoparticles (NPs) with average diameter of 38 and 10 nm were prepared in advance through a chemical solution method. Pd-functionalized ZnO nanoparticles (Pd@ZnO) were simply synthesized by adding ethanol solution of Pd NPs into ZnO powder, and annealing in argon atmosphere at 500 °C for 1 h after grinding for 30 min. The morphology and structure of the materials were systemically analyzed using Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) techniques. A weak peak in the XRD pattern of Pd@ZnO belonging to the (111) plane of elemental Pd indicated successfully loading of Pd. EDS and TEM results further confirmed successfully coating of Pd NPs onto the surface of ZnO. Sensors using ZnO NPs decorated with Pd (1 wt%) on the surface of exhibited highly elevated sensitivity of 76 in comparing with the response of 36 when based on pure ZnO NPs. In addition, such modification also resulted in a decrease in the operating temperature from 370 to 340 °C for 100 ppm acetone vapor. The sensing mechanism of the sensor based on Pd@ZnO NPs is discussed. Addition of Pd NPs can play an important role in improving the performance of gas sensors, including high sensitivity, good selectivity, and short response/recovery times.  相似文献   
16.
The reaction of pyridine-2,5-dicarboxylic acid with Sc2O3 under hydrothermal con-dition yields a new complex [Sc(μ-OH)(2,5-pydc)(H2P)]n 1 which has a chain structure based on homodinuclear scandium units. Crystal data for 1: space group P1, a = 6.7192(13), b = 7.6131(13),c= 8.9313(14) A, α = 95.976(6), β = 101.663(6),γ,= 108.151(5)°, V = 418.26(13) A3, Z = 2, Dc =1.946 g/cm3,μ = 0.889 mm-1, F(000) = 248, C7H6NO6Sc, M, = 245.09, the final R = 0.0429 and wR = 0.1086.  相似文献   
17.
The reaction of pyridine-2,5-dicarboxylic acid with Sc2O3 under hydrothermal con- dition yields a new complex [Sc(μ-OH)(2,5-pydc)(H2O)]n 1 which has a chain structure based on homodinuclear scandium units. Crystal data for 1: space group P^-1, a = 6.7192(13), b = 7.6131(13), c = 8.9313(14) A, α = 95.976(6), β = 101.663(6), γ = 108.151(5)^o, V= 418.26(13) A^3, Z = 2, Dc = 1.946 g/cm^3, g = 0.889 mm^-1, F(000) = 248, C7H6NO6Sc, Mr = 245.09, the final R = 0.0429 and wR = 0.1086.  相似文献   
18.
Polyureas(PU) are well known as a class of high impact engineering materials, and widely used also in emerging advanced applications. As a general observation, most of them are only soluble in a very limited number of highly protonic solvents, which makes their chemical structure analysis a great challenge. Besides the presence of abundant hydrogen bonding, the poor solubility of PU in common organic solvents is often ascribed to the formation of biuret crosslinking in their molecular chains. To clarify the presence of biuret groups in PU has been of great interest. To this end, two samples, based on hexamethylene diisocyanate(HDI) and toluene diisocyanate(TDI) respectively, were synthesized by precipitation polymerization of each of these diisocyanates in water-acetone at30 °C. Their chemical structures were analyzed by high resolution magic angle spinning(HR-MAS) NMR, and through comparison of their NMR spectra with those of specially prepared biuret-containing polyurea oligomers, it was concluded that biuret group was absent in all the PU prepared at 30 °C. In addition, this NMR analysis was also applied to a PU obtained by copolymerization of TDI with ethylene diamine(EDA) and water at 65 °C in EDA aqueous solution. It was confirmed that biuret unit was also absent in this PU and that EDA was more active than water towards TDI. The presence of EDA was crucial to the formation of uniform PU microspheres. This study provides therefore a reliable method for the analysis of PU chemical structure.  相似文献   
19.
20.
A binicotinic biscarbohydrazone compound,2,2'-bipyridyl-3,3'-bis(N,N'-disali- cylidene)-formyhydrazone,1 has been prepared and characterized by elemental analysis,FT-IR,1H- NMR,ESI-MS and single-crystal X-ray diffraction analysis. The crystal belongs to triclinic,space group P1 with a = 9.419(3),b = 11.745(4),c = 12.035(5)A,V = 1178.8(7)A^3,Z = 2,Dc = 1.354 g/cm^3,μ = 0.095 mm^-1,F(000) = 500,λ(MoKα) = 0.71073 ,C26H20N6O4,Mr = 480.48,the final R = 0.0480 and wR = 0.1084 for 3634 observed reflections with I 〉 2σ(I). Single-crystal X-ray diffraction analysis reveals that a 1D supramolecular structure of 1 has been constructed by multiply intermolecular N–H···N and O–H···O H-bonding interactions. Besides,compound 1 exhibits a strong green-light emission in the solid state at room temperature.  相似文献   
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