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1.
在碱性介质中只有少数氧化剂如Ag(Ⅲ)及Cu(Ⅲ)仍有较强的氧化性,因此研究Ag(Ⅲ)、Cu(Ⅲ)络合物阴极还原的电极电势、电子转移数及还原机理,对于深入了解它们作为氧化剂时的氧化还原特性是有帮助的.本文用薄层光谱电化学方法测定了二过碘酸合银(Ⅲ)、络离子在不同pH条件下还原反应的E~0′和电子转移数(n),并由此推断阴极还原反应机理,还用同样方法研究了二过碘酸含铜(Ⅲ)络离子的阴极还原.  相似文献   

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A new method of synthesizing single-component molecular conductor [Ni(dmit)2] bythe reaction 2(Me4N)[Ni(dmit)2]2→ [Ni(dmit)2] (Me4N)[Ni(dmit)2] is reported. [Ni(dmit)2]exhibits a semiconductive behavior above 167 K, while from 167 K down to the measuring limit of 60 K, it exhibits metallic conductivity.  相似文献   

4.
用微量热法对菲洛合铜[Cu(phen)2]2^2 和联吡合铜[Cu(bpy)2]^2 与小牛胸腺DNA的相互作用进行了研究,依据McGhee-Von Hippel邻近排斥方程确定了结合反应的平衡常数K、结合位点距离n及热力学参数 △rHm,△rGm和△rSm。结果表明这两种铜的配合物与DNA之间均可 形成稳定的三元配合物,且反应为熵驱动过程,DNA与这些配合物的刍合过程中同时存在插入和静电作用两种模式,插入作用的强弱与金属配合物中配体的平面性质有关。  相似文献   

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A new bismuth (III) iodate periodate, Bi2(IO3)(IO6) was obtained from hydrothermal reactions using Bi(NO3)3·5H2O, and H5IO6 as starting materials. Bi2(IO3)(IO6) crystallizes in the monoclinic space group P21/c (No. 14) with lattice parameters ɑ = 8.1119(6), b = 5.4746(4), c = 16.357(1) Å, β = 99.187(2)°, V = 717.07(9) Å3, Z = 4. The structure of Bi2(IO3)(IO6) features a three-dimensional framework which is a combination of [Bi(1)O5] tetragonal pyramids, [Bi(2)O8] bicapped trigonal prisms and [IO3] and [IO6]5− anions. Thermal analysis shows that the compound is thermally stable up to about 350 °C. The solid state UV-vis-NIR diffuse reflectance spectrum indicates that Bi2(IO3)(IO6) is a semiconductor with a band gap of 2.76 eV.  相似文献   

6.
在不同的温度下,考察了六氰合铁配阴离子「Fe(CN)5」^4-还原trans-「Co(en)2(ImH02」^3+的反应动力学。结果表明,反应遵循H.Taube所提出的外配位界电子传递机理。在25℃,I=0.5mol.L^-1,trans-「Co(en)2(ImH)2」^3+/「Fe(CN)6」^4-反应体系的前驱配合物离子对形成常数为Q1p=98.9mol^-1.L,电子转移速率常数为Km=1.  相似文献   

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(NH3CH2CH2NH2)3[Mo(Ⅴ)O2(O2C6H4)2] (1), (NH3CH2CH2NH2)2.5[Mo(Ⅴ)o.sW(Ⅵ)o.502(O2C6H4)2] (2) and(NH3CH2CH2NH2)2[VC(Ⅵ)O2(O2C6H4)2] (3) were synthesized, structurally characterized by X-ray diffraction analysis, and studied on their interactions with ATP, their DNA cleavage activities and antitumor properties. The redox state of molybdenum was not changed on going from crystal to aqueous solutions in complexes 1 and 2, while tungsten underwent reduction from W(VI) to W(V) in complexes 2 and 3. ATP promoted the oxidation of both molybdenum and tungsten from M(Ⅴ) to M(Ⅵ) and the hydrolysis of catecholate ligands in solution consisting of ATP and the complexes. Complex 1 possesses fairly good activity to DNA cleavage and against tumor S180 in mice, and is more effective than the control drug cyclophosphamide under the identical conditions. However, complexes 2 and 3 exhibited marginal effectiveness. The effectiveness of anti-tumor of the complexes was related positively to their DNA cleavage activities and their hydrolysis of catecholate ligands.  相似文献   

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Synthesis and Crystal Structure of [ReNCl(NPPh2C6H4)]2 · [Ph3PNH2]Cl · CH3CN, a Rhenium Organic Nitrido Phosphoraneiminato Complex The title compound is synthesized by the reaction of ReNCl4 with Me3SiNPPh3 in boiling acetonitrile, forming colourless crystals, which are characterized by an X-ray structure determination. Space group P1 , Z = 2, 4 037 observed unique reflections, R = 0.043. Lattice dimensions at 19°C: a = 1 005.5; b = 1 695.2; c = 1 744.7 pm, α = 105.86°; β = 101.49°; γ = 104.45°. The structure consists of dimeric molecules [ReNCl(NPPh2C6H4)]2, triphenylphosphorane ammoniumchloride and included acetonitrile molecules. In the nitrido phosphoraneiminato complex the rhenium atoms are μ2-bridged via the N-Atoms of the phosphoraneiminato ligands. Because of this bridging and a Re? Re bond, one terminal nitrido ligand, one terminal chloro ligand, and a Re? C bond of an -C-atom of one phenylene group of Re-atoms attain co-ordination number six.  相似文献   

12.
CommentDuringinvestigationsonvariousmetalcomplexeswithH鄄Norf[1,2],complexationwithBiwasinvestigated.Fig.1showsthestructureofthefirstBi髥complexcontainingtheantibacterialdrugNorfloxacin○,[Bi2Cl10(H2鄄Norf)4(H2O)8].Thisisanioniccompoundcompris鄄ingfour[H2  相似文献   

13.
Synthesis and Crystal Structure of [Na(12-Crown-4)2]2[Hg(Se4)2] · 1.5 DMF . The title compound has been prepared by the reaction of Na2Se4 with mercury acetate in DMF solution in the presence of 15-crown-5, forming dark red crystal needles. [Na(12-crown-4)2]2[Hg(Se4)2] · 1.5 DMF crystallizes in the space group C2/c with eight formula units per unit cell. The structure was determined with 3 824 observed unique reflections, R = 0.085. Lattice dimensions at - 70°C: a = 2 884(2), b = 1 407.7(7), c = 2 843(2) pm, β = 93.93(5)°. The structure consists of [Na(12-crown-4)2]+ ions with a sandwichlike coordination of the crown ether molecules, and of [Hg(Se4)2]2? ions, in which the mercury atom is coordinated by two tetraselenido ions in a chelating fashion. The [Hg(Se4)2]2? ions are arranged to infinite chains via Se…?Se contacts.  相似文献   

14.
Syntheses and Crystal Structures of the Thiochloroantimonates(III) PPh4[Sb2SCl5] and (PPh4)2[Sb2SCl6]. CH3CN (PPh4)2Sb3Cl11, obtained from Sb2S3, PPh4Cl and HCl, reacts with Na2S4 in acetonitrile forming PPh4[Sb2SCl5]. From this and Na2S4 or from (PPh4)2[Sb2Cl8] and Na2S4 or K2S5 in acetonitrile (PPh4)2[Sb2SCl6] · CH3CN is obtained. Data obtained from the X-ray crystal structure determinations are: PPh4[Sb2SCl5], monoclinic, space group P21/c, a = 1002.9(3), b = 1705.6(5), c = 1653.7(5) pm, β = 99.12(2)°, Z = 4, R = 0.068 for 1283 reflextions; (PPh4)2[Sb2SCl6] · CH3CN, triclinic, space group P1 , a = 1287.8(7), b = 1343.6(9), c = 1696.5(9) pm, α = 69.82(5), β = 85.08(4), γ = 71.54(6)°, Z = 2, R = 0.059 for 6409 reflexions. In every anion two Sb atoms are linked via one sulfur and one ore two chloro atoms, respectively. Paris of [SbSCl5]? ions are associated via Sb …? S and Sb …? Cl contacts forming dimer units. In both compounds every Sb atom has a distorted octahedral coordination when the lone electron pair is included in the counting.  相似文献   

15.
The brown crystals of [PMePh3]2[Se2Br6] ( 1 ) and red crystals of [PMePh3]2[SeBr6(SeBr2)2] ( 2 ) were obtained when selenium and bromine reacted in the solution of acetonitrile in the presence of methyltriphenylphosphonium bromide. The crystal structures of 1 and 2 has been determined by the X‐ray methods and refined to R = 0.0373 for 2397 reflections and 0.0397 for 3417 reflections, respectively. The salt 1 crystallizes in the monoclinic space group P21/n with the cell dimensions a = 13.202(5) Å, b = 11.954(4) Å, c = 13.418(6) Å, β = 93.08(4)° (193(2)). The crystals of 2 are triclinic, space group with the cell dimensions a = 10.266(3) Å, b = 11.311(3) Å, c = 11.619(2) Å, α = 108.87(2)°, β = 105.72(2)°, γ = 99.40(2)° (193(2) K). In the solid state structure of 1 the dinuclear hexabromo‐diselenate(II) anion is centrosymmetric and consists of two distorted almost square planar SeBr4 units sharing a common edge through two μ‐bridging Br atoms. The terminal SeII–Br bonds are 2.3984(11) and 2.4273(11) Å, whereas the bridging μBr–SeII bonds are 2.7817(11) and 2.9081(12) Å. In the solid state the trinuclear [SeBr6(SeBr2)2]2? anion of 2 is centrosymmetric too and contains a nearly regular [SeBr6] octahedron where the four equatorial bromo ligands each have developed bonds to the SeII atoms of the SeBr2 molecules. The contacts between the bridging bromo and the SeII atoms of the SeBr2 molecules are 3.0603(15) and 3.1043(12) Å, and can be interpreted as bonds of the donor‐acceptor type with the bridging bromo ligands as donors and the SeBr2 molecules as acceptors. The SeIV–Br distances are in the range 2.5570(9)–2.5773(11) Å and the SeII–Br bond lengths in coordinated SeBr2 molecules – 2.3411(12) and 2.3421(10) Å.  相似文献   

16.
On the Crystal Structures of the Cyano Complexes [Co(NH3)6][Fe(CN)6], [Co(NH3)6]2[Ni(CN)4]3 · 2 H2O, and [Cu(en)2][Ni(CN)4] Of the three title compounds X‐ray structure determinations were performed with single crystals. [Co(NH3)6][Fe(CN)6] (a = 1098.6(6), c = 1084.6(6) pm, R3, Z = 3) crystallizes with the CsCl‐like [Co(NH3)6][Co(CN)6] type structure. [Co(NH3)6]2[Ni(CN)4]3 · 2 H2O (a = 805.7(5), b = 855.7(5), c = 1205.3(7) pm, α = 86.32(3), β = 100.13(3), γ = 90.54(3)°, P1, Z = 1) exhibits a related cation lattice, the one cavity of which is occupied by one anion and 2 H2O, whereas the other contains two anions parallel to each other with distance Ni…Ni: 423,3 pm. For [Cu(en)2][Ni(CN)4] (a = 650.5(3), b = 729.0(3), c = 796.5(4) pm, α = 106.67(2), β = 91.46(3), γ = 106.96(2)°, P1, Z = 1) the results of a structure determination published earlier have been confirmed. The compound is weakly paramagnetic and obeys the Curie‐Weiss law in the range T < 100 K. The distances within the complex ions of the compounds investigated (Co–N: 195.7 and 196.4 pm, Ni–C: 186.4 and 186.9 pm, resp.) and their hydrogen bridge relations are discussed.  相似文献   

17.
将医用药物异丙肾上腺素引入分析化学作新显色剂,报道了异丙肾上腺素与[Fe(CN)6]3-进行显色反应的最佳条件、灵敏度、选择性和允许共存比.建立了微量的[Fe(CN)6]3-简便检定新方法,检出限为0.055μg,稀释限为14.5×106.  相似文献   

18.
Crystal Structures of [Ph3PMe]Cl·CH2Cl2, [Ph4P]NO3·CH2Cl2, and [Ph4P]2[SiF6]·CH2Cl2 The crystal structures of the title compounds are determined by X‐ray diffraction. In all cases, the included dichloromethane molecules as well as the phosphonium cations are involved to form hydrogen bridges with the anions. [Ph3PMe]Cl·CH2Cl2 ( 1 ): Space group , Z = 2, lattice dimensions at 100 K: a = 890.3(1), b = 988.0(1), c = 1162.5(1) pm, α = 106.57(1)°, β = 91.79(1)°, γ = 92.60(1)°, R1 = 0.0253. [Ph4P]NO3·CH2Cl2 ( 2 ): Space group P21/n, Z = 4, lattice dimensions at 193 K: a = 1057.0(1), b = 1666.0(1), c = 1358.9(1) pm, β = 100.10(1)°, R1 = 0.0359. [Ph4P]2[SiF6]·CH2Cl2 ( 3 ): Space group , Z = 2, lattice dimensions at 193 K: a = 1063.9(1), b = 1233.1(1), c = 1782.5(2) pm, α = 76.88(1)°, β = 83.46(1)°, γ = 72.29(1)°, R1 = 0.0332.  相似文献   

19.
Cylindrospermopsin (CYN) was determined by liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) using 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid (HEPES) as the internal standard. In the selected ion monitoring of LC/ESI-MS, m/z 414 for CYN and 237 for HEPES were monitored using the negative mode; the retention times of CYN and HEPES were 12.41 and 14.21 min, respectively. CYN was determined from peak area ratios of m/z 414/237. By the treatment of an anion exchange cartridge using a buffer at pH 10.5, CYN was isolated and condensed. No interfering peak was observed. Linearity of this method was observed at the range of 0.10-31.12 ng. Total coefficients of variation were 5.1 and 2.9% at 104 and 1038 μg CYN L−1. The quantitative limit at a signal-to-noise (S/N) ratio of 10 was 0.16 ng.CYN concentration in natural waters is low. CYN in waters should be condensed for determination. This method including the treatment for isolation and condensation of CYN is useful for determination of CYN in environmental and/or drinking waters.  相似文献   

20.
The reaction of (Bu4N)2[Mo6O19] with 8-aminoquinoline in the presence of DCC (N,N′-dicyclohexylcarbodiimide) afforded the cis-dioxo-Mo(VI) amide [MoO2(NHC9H6N)2], which was characterized by spectroscopy, mass spectrometry, 1H NMR, and single-crystal X-ray analysis. X-ray crystallography shows that the complex exhibits a distorted octahedral geometry with each oxo ligand trans to the quinolyl nitrogen and the amido ligands are bound to the metal in an N,N-chelating fashion. The molecules form zigzag chains via C–H?···?O hydrogen bonds and the chains are connected into networks through interchain N–H?···?O hydrogen bonds.  相似文献   

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