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1.
1 INTRODUCTION The polymeric metal complexes with extended structures are of great interest because of their useful chemical or physical properties[1]. Due to the noticeable fact that the aromatic polycarboxylate can provide versatile coordination mode and the non-coplanar structure of the carboxylate groups and the benzene rings, a lot of efforts in this field have been particularly directed to the preparation of aromatic polycarboxylate (such as phthalate, tere- phthalate and isophthal…  相似文献   

2.
章慧 《大学化学》1996,11(2):49-52
结合对[Co(NH3)5Cl]^2)与[Co(NH3)6]^3+的颜色的比较,阐述配体场理论中有关电子组态、能级、轨道、配体场谱项及谱项间跃迁等基本概念及难点。即使不做严格的量子化学计算,从直观的物理模型、简单的分子轨道理论、群论方法及有关谱图中也能获得有用信息。  相似文献   

3.
The title complex [Co(TPPO)_4] [Co(NCS)_2TPPO]_2 (TPPO=triphenylphosphine oside) was prepared by solvent evaporation method. Its crystal structure was determined by x-ray diffraction method. The crystal is rhombohedral with space group R3. The unit cell parameters are presented and the structure has been refined to a final R of 0.064.  相似文献   

4.
A sterically encumbered 'tritopic' picolinic-dihydrazone ligand reacts with cobalt(ii) nitrate in air to give a dodecanuclear [Co(ii)(6)Co(iii)(6)] cluster, in which six ligands are hydrolyzed to mono-carboxylate analogues.  相似文献   

5.
The isomerization products of fac- and mer-[Co(β-ala)_3] in neutral and acidic media were separated with Na~+-type SP-Sephaex C-25 column and determined by spectrophotometry. At high temperatures(>90 ℃)the fac-isomer readily isomerizes to mer-[Co(β-ala)_3] and simultaneously hydrolyzes to yield a brown slurry in neutral solution.However, in acidic solution hydrolysis does not occur, the products are mer-isomer and a small amount of red complex cation, which is strongly adsorbed at the top of SP-Scphadex column and would probably be the fac-[Co(β-ala)_2[Co(β-alaH)(H_2O]~+.At 90 ℃ the mer-[Co(β-ala)_3]is hydrolyzed rapidly to yield a brown precipitate in neutral solution and isomerizes in small amount to fac-isomer. In acidic solution the mer-isomer isomerizes slightly to fac-isomer, and at the top of SP-Sephadex column, a violet complex cation which would probably be mer-[Co(β-ala)_2(β-alaH)(H_2O]~+ is abserved.The kinetic parameters of isomerization of fac-[Co(β-ala)_3] in neutral, basic and acidic solutions have been determined with spectrophotometric method at 534 nm. The resufts obtained indicate that reaction rates v with respect to fac-[Co(β-ala)_3] in neutral, basic and acidic media are all in first order, and under constant initial concentration of fac-[Co(β-ala)_3] the reaction rates v with respect zation of fac-[Co(β-ala)_3] in neutral, [OH~-]=4.04×10~(-4) molL~(-1), [HCl]=1.56×10~(-2) molL~(-1) and [HClO_4]=1.56×10~(-2) molL~(-1) media at 90 ℃ are 0.0195, 57.3, 3.43 and 0.978 min~(-1) while the activation energies are 194.2, 103.1, 134.1 and 113.8 kJ.mol~(-1) respectively.  相似文献   

6.
Compounds that form in the CoSiF6· 6H2O–NioxH2–A–water–alcohol system, where A is thiourea (Thio) or triphenylphosphine (PPh3) and NioxH2is 1,2-cyclohexanedione dioxime, were synthesized and characterized by X-ray diffraction analysis. Crystal structures of the [Co(NioxH)2(PPh3)2]SiF5and [Co(NioxH)2(Thio)2]2SiF6· 3H2O complexes were established. In octahedral Co(III) complexes, two radicals of 1,2-cyclohexanedione dioxime are bound by a hydrogen bond and are located in the equatorial plane. The intramolecular (– and H bonds) and intermolecular (C–H···F and H bonds) interactions in the crystal are discussed.  相似文献   

7.
The structure of the title compound features mononuclear octahedral CoII cations, trans-[Co(H2O)2(MeCN)4]2+, and trinuclear anions, trans-[Co(H2O)2(MeCN)2(CoCl4)2]2–; the latter centrosymmetric units contain a central octahedral Co(H2O)2(MeCN)2 moiety with two tetrahedral [CoCl4]2– ligands. These two large ions are held in a network of intra- and inter-molecular hydrogen bonding.  相似文献   

8.
Crystal structures of [Co(MH)2(Thio)2][BF4] · H2O (I) and [Co(DH)2(NH3)2][BF4] (II), where MH is H3C–C(NOH)–C(NO)–H and DH is H3C–C(NOH)–C(NO)–CH3, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N4S2 for I and N6 for II. In the crystals of I and II, the complex cations and the outer-sphere [BF4] anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.  相似文献   

9.
水热条件下合成了一个新的有机二膦酸钴配合物[Co(en)3][Co2(Hedbbp)2].7H2O,[H4edbbp=N,N’-二(苄基膦酸)乙二胺].X射线单晶衍射结构分析表明:配合物属三斜晶系,空间群P,ī晶胞参数:a=1.505.6(3)nm,b=1.524 8(3)nm,c=1.649 7(3)nm,α=63.10(3)°,β=78.12(3)°,γ=75.62(3)°,晶胞体积为V=3.252 4(11)nm3,Z=2.配合物结构单元中包含一个二膦酸钴的二聚单元阴离子[Co2(Hedbbp)2]2-和一个三乙二胺合钴螯合阳离子单元[Co(en)3]2 和七个水分子.  相似文献   

10.
[Co(β-ala)_3]有经式(mer-)和面式(fac-)两种几何异构体。它们的合成、分离、表征和拆分已有人作过研究,但在溶液中的异构化反应动力学未被研究过。本文的目的是研究这两几何异构体在不同介质中的相互转化的动力学,并根据所得结果来探讨fac-、mer-[Co(β-ala)_3]的合成条件。  相似文献   

11.
[Co(phen)3]2[PMo12O40](OH)的水热合成及晶体结构   总被引:1,自引:0,他引:1  
利用水热合成法制备了Keggin结构阴离子有机一无机复合物[Co(phen)3]2[PMo12O40](OH),通过元素分析,红外光谱和X射线单晶衍射等对其进行了表征.结果表明,该化合物属于单斜晶系,C2/c空间群.=1.97225(18)nm,b=1.81079(16)nm,c=2.5117(2)nm,β=100.5380(10)°,V=8.819O(14)nm^3,Z=4,R1=0.0587,wR2=0.1211.该化合物分子由一个多阴离子[PMo12O40]^3-,两个[Co(phen)3]^2+及一个羟基组成.  相似文献   

12.
CRYSTAL AND MOLECULAR STRUCTURE OF [K(C_(14)H_(20)O_5)_2]_2[Co(NCS)_4]   总被引:1,自引:0,他引:1  
<正> The title complex (Mr= 1442.6) crystallizes in the monoclinic, space group PC, with a =14.515(7),b =15.773(5), c =16.287(11)51,β=95.13(5)°,Z=2,V=3713.8A3,Dc=1.29 g·cm-3. The structure was solved by Patterson method and the final R=0.068. The potassium atom in the cation lies between the two planes of the oxygen atoms from two benzo-15-crown-5 molecules.  相似文献   

13.
水热条件下合成了一个新的有机二膦酸钴配合物[Co(en)3][Co2(Hedbbp)2]·7H2O,[H4edbbp=N,N'-二(苄基膦酸)乙二胺].X射线单晶衍射结构分析表明配合物属三斜晶系,空间群P-1,晶胞参数a=1.505.6(3)nm,b=1.524 8(3)nm,c=1.649 7(3)nm,α=63.10(3)°,β=78.12(3)°,γ=75.62(3)°,晶胞 体积为V=3.2524(11)nm3,Z=2.配合物结构单元中包含一个二膦酸钴的二聚单元阴离子[Co2(Hedbbp)2]2-和一个三乙二胺合钴螯合阳离子单元[Co(en)3]2+和七个水分子.  相似文献   

14.
Binary complex salts, [Co(En)3][Fe(CN)6] · 2H2O and [Co(En)3]4[Fe(CN)6]3 · 15H2O, are synthesized. The properties of the salts and their thermolysis in air, dihydrogen, and argon are studied. Oxides of the central ions of the binary complex salts are found to be the thermolysis products in an oxidative atmosphere. Solid solutions (intermetallic compounds) CoFe are the thermolysis products in the reductive atmosphere, whereas intermetallides containing considerable amounts of C and N and an impurity of Co and Fe oxides are the thermolysis products in an inert atmosphere. Gaseous thermolysis products in dihydrogen and argon are NH3, hydrocarbons, and ethylenediamine.  相似文献   

15.
A new organic-inorganic hybrid polyoxometalate based on Dawson-like polyoxotungstate anion [SbW18O60]9, formulated [Co(2,2′-bpy)3]2[Co(2,2′-bpy)2Cl][Co(2,2′-bpy)2]H2[SbW18O60]·4H2O (2,2′-bpy= 2,2′-bipyridine) has been synthesized from Sb2O3, Na2WO4, CoCl2, and 2,2′-bipyridine materials by hydrothermal method, and which was characterized by elemental analyses, IR, XPS, EPR, TG, and X-ray single crystal diffraction. Structure analysis shows that the polyoxoanion self-assembled under hydrothermal conditions consists of a Dawson-like polyoxotungstate cluster anion [SbW18O60]9 en- capsulating a pyramidal {SbO3} group within the {W18} cluster cage. EPR spectra show that the high-spin octahedral CoII and low-spin CoII ions coexist in the title compound. Magnetic properties in- dicate that the compound is antiferromagnetic.  相似文献   

16.
An X-ray diffraction analysis of [Co(HEdda)En(CN)]HgCl3 crystals (a = 6.664(4), b = 16.613(13), c = 16.684(7) å, space group P212121, Z = 4) showed that the crystals contain distorted tetrahedra HgCl4 linked by one of their vertices into infinite chains [HgCl3] n n- . In isolated complex cations, three donor atoms of the HO2CCH2NHCH2CH2NHCH2CO 2 - (HEdda) ion occupy a face of the coordination octahedron around the cobalt atom; the opposite face is occupied by the cyanide ion and the nitrogen atoms of the ethylenediamine (En) molecule; the latter are in trans positions relative to the terminal donor atoms of the HEdda ligand.  相似文献   

17.
A variety of electrochemical reactions has been observed for the carbido-carbonyl clusters [Co8(CO)18C](NMe3CH2C6H5)2, [Co6(CO)15C](NMe3CH2C6H5)2, [Rh6(CO)15C](Et4N)2 and [Fe6(CO)16C](Et4N)2. The hexanuclear clusters undergo irreversible electrochemical oxidation and reduction steps, whereas the octacobalt species exhibits three electrochemically reversible one-electron steps. The relation between the redox properties and the structure of these clusters is discussed.  相似文献   

18.
A new organic-inorganic hybrid polyoxometalate based on Dawson-like polyoxotungstate anion [SbW18O60]9-, formulated [Co(2,2'-bpy)3]2[Co(2,2'-bpy)2Cl][Co(2,2'-bpy)2]H2[SbW18O60]·4H2O (2,2'-bpy= 2,2(-bipyridine) has been synthesized from Sb2O3, Na2WO4, CoCl2, and 2,2'-bipyridine materials by hydrothermal method, and which was characterized by elemental analyses, IR, XPS, EPR, TG, and X-ray single crystal diffraction. Structure analysis shows that the polyoxoanion self-assembled under hydrothermal conditions consists of a Dawson-like polyoxotungstate cluster anion [SbW18O60]9- encapsulating a pyramidal {SbO3} group within the {W18} cluster cage. EPR spectra show that the high-spin octahedral CoⅡ and low-spin CoⅡ ions coexist in the title compound. Magnetic properties indicate that the compound is antiferromagnetic.  相似文献   

19.
在不同的温度下,考察了六氰合铁(Ⅱ)配阴离子[Fe(CN)6]4-还原trans-[Co(en)2(ImH)2]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,电子转换速率常数为Ket=1.3×10-4s-1,电子转移过程活化焓ΔH≠et和活化熵ΔS≠et分别为141.2kJ·mol-1、573.5J·mol-1·K-1。  相似文献   

20.
The title compound [Co3(CO)9(μ3-C)C(O)OCH2]2 was synthesized by the reaction of [Cl3CC(O)OCH2]2 with Co2(CO)8 at 40~50 ℃. Crystal data: C24H4O22Co6, Mr=997.88, monoclinic, space group P21/n(#14), a=9.330(2), b=15.197(4), c=11.783(4), β=91.16(2)°, V=1670.4(7) 3, Z=2, Dc=1.984 g/cm3, μ(MoKα)=30.01 cm-1, F(000)=972.00, T=293K, final R=0.045, Rw=0.051 for 1936 observed reflections with I>2σ(I). The structure contains two centrosymmetric dimeric molecules in a unit cell, each of which has two tetrahedral skeletons (CCo3) connected through a C(O)OCH3CH2OC(O) bridge.  相似文献   

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