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1.
用键共振能和拓扑共振能方法对富勒烯C36CH2开环结构中的所有可能异构体及其阳离子和阴离子芳香性进行了研究. 计算结果表明, C36CH2异构体的稳定性与D6hD2d异构体中各键的键共振能直接有关, 且CH2基团插入在5/5键时得到的异构体最稳定. C36CH2的阳离子因其共振能为负值而具有反芳香性. 反之, C36CH2阴离子因共振能为正值而具有较高的芳香性和稳定性. 从理论上预计C36CH2的高价阴离子具有很高的芳香性和稳定性.  相似文献   

2.
新颍Mo-Cu-Se簇合物{MoCu3Se3I}(PPh3)3O·0.5CH2Cl2是由[Et4N]2MoSe4、Cu(PPh3)2NO3和KI在乙腈和二氯甲烷1∶1的混合溶剂中反应所得。晶体属单斜晶系,空间群P21相似文献   

3.
用INDO系列方法研究C78(CH2)2的18种可能异构体,表明最稳定异构体是42,43,62,63-C78(CH2)2,其中CH2加在C78(C2V)椭球长轴所穿过的同一六员环的两个6/6键上,形成类环丙烷结构。并对最稳定的四种异构体用B3LYP/3-21G方法进行了结构优化,在此基础上, 用INDO/CIS方法计算的C78(CH2)2稳定异构体的电子光谱的第一吸收峰和用AM1方法计算的碳笼上的C-C键的主要红外振动频率与C78(C2V)相比发生兰移,原因是C78(CH2)2具有较大的LUMO-HOMO能隙和由于加成带来的共轭体系变小。在B3LYP/3-21G水平上计算的13C NMR谱表明,被加成的C-C键上的C原子化学位移向高场移动, 这是因为sp2杂化的C 原子被转化为 sp3杂化的C 原子.  相似文献   

4.
鲁晓明  宋富根  王波  李丽 《无机化学学报》2005,21(11):1687-1690
Cis-dioxo-catecholatotungsten(Ⅴ) complex (NH2CH2CH2NH3)4[WO2(OC6H4O)2]2(NH3CH2CH2NH3)·H2O (1) was synthesized at room temperature by the reaction of tetrabutyl ammonium decatungstate with catechol in the mixed solvent of CH3OH, CH3CN and NH2CH2CH2NH2. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21/c,a=0.712 8(3) nm, b=3.082 3(11) nm, c=0.982 8(4) nm, β=102.639(6)°, V=2.106 8(14) nm3, Z=2, R1=0.062 8, wR2=0.183 7. Compared the complex with its analogous complexes (NH2CH2CH2NH3)3[MoO2(OC6H4O)2], it is found that the coordination structure of W have no changes in the processing of electron transfer of tungsten-containing enzymes from the result of the similarity of the EPR spectra of the complexes and flavoenzyme from milk. CCDC: 272937.  相似文献   

5.
C60Co(Pph3)2的合成和表征   总被引:1,自引:0,他引:1  
The fullerene complexe C60Co(Pph3)2 has been prepared by the reaction of C60 with CoCl2(Pph3)2 under a nitrogen atmosphere and refluxing, and characterized by elemental analyses, FT-IR, XPS, NMR, which appove that C60 coordinates to Co(Pph3)2 group in σ-π pattern and the electron is super conjugate over whole molecule. The result of redox property study show that the reduction potentiel of C60Co(Pph3)2 is more negative than that of C60, the reason may be the π electron dentensity of C60 in C60Co(Pph3)2 increases, which lead to it′s electron affinity decreasing. The thermostability experiment indicates that the oxidation decomposition temperature of C60Co(Pph3)2 is lower than that of pure C60.  相似文献   

6.
The crystal of Ag2[Ph2(CH2)2Ph2l4(NO3·CH3OH)2 is monoclinic, space group P21/n, with a=14.741, b= 19.042, c= 18.982Å;β = 110.66°. The molecule has a 21 symmetry axis. The four dppe ligands are coordinated in two ways, two ligands bridging the two silver atoms, and the other two ligands chelate to each silver atom separately to form two penta-cycles.  相似文献   

7.
用X-射线衍射法测定了[C5H4C(CH3)(C3H7)CH2CH=CH2]NdMg2(μ3-OH)(μ3-Cl)(μ2-Cl)3(THF)4Cl的晶体结构。它属三斜晶系,空间群为<  相似文献   

8.
以母体配合物[Fe2(CO)6(μ-SCH2CH(CH2CH3)S)](1)分别与三(2-呋喃基)膦、二苯基丙基膦、双(二苯基膦)乙炔、1,2-双(二苯基膦基)苯和脱羰试剂Me3NO·2H2O反应,制备了单取代配合物[Fe2(CO)5(L)(μ-SCH2CH(CH2CH3)S)](L=P(2-C4H3O)3,2;Ph2PCH2CH2CH3,3)、桥联配合物{[Fe2(CO)5(μ-SCH2CH(CH2CH3)S)]2(Ph2PC≡CPPh2)}(4)和螯合配合物[Fe2(CO)4(κ2-(Ph2P)2(1,2-C6H4))(μ-SCH2CH(CH2CH3)S)](5)。配合物2~5经元素分析、红外光谱、核磁共振氢谱和磷谱表征,并进一步得到单晶X射线衍射的确证。电化学研究表明,在弱酸HOAc作为质子源存在的情况下,这些配合物可以实现催化质子还原产生氢气的功能。  相似文献   

9.
Cis-dioxo-tungsten(Ⅵ) complex, (NH2CH2CH2NH2)[(NH2CH2CH2NH3)2WO2(NHC6H4NH)2]2·H2O is synthesized at room temperature by the reaction of sodium tungstate with o-phenylenediamine. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21/ c, a=0.712 8(2) nm, b=3.081 1(10) nm, c=0.981 9(3) nm, β=102.615(4)°, V=2.104 4(11) nm3, Z=2, μ=55.26 cm-1, F(000)=1 176. Compared the complex with its analogous biomimetic complexes of the cofactor of molybdoenzymes and tungstoenzymses, it is found that the variance of the coordination atoms and the metal ions center have no influence on the coordination feature, and exhibits distored octahedral coordination with cis-dioxo o-phenylenediamine. CCDC: 252834.  相似文献   

10.
钌配合物催化氢化CO2生成甲酸反应中的醇促进效应   总被引:1,自引:0,他引:1  
在水合钌配合物[TpRu(PPh3)2(H2O)]BF4 [Tp=hydrotris(pyrazolyl) borate]催化氢化二氧化碳生成甲酸的反应中观察到醇对反应的促进作用. 利用原位高压核磁共振跟踪催化反应过程的结果表明, 在甲醇溶液中, [TpRu(PPh3)2(H2O)]BF4在三乙胺和H2作用下转化为TpRu(PPh3)2H. 二氧化碳插入Ru—H生成甲酸根配合物TpRu(PPh3)2(η1-OCHO)•HOCH3, 其中的甲酸根配体与醇分子间形成分子间氢键. 该甲酸根配合物随即转化为另一个甲酸根配合物TpRu(PPh3)(CH3OH)(η1-OCHO)并与之达成平衡, 后者由于存在分子内氢键而稳定. 考虑到这两个甲酸根配合物在催化反应中的稳定性, 它们应该不在主要的催化循环内. 提出了配合物[TpRu(PPh3)2(H2O)]BF4在几种醇溶液中催化氢化二氧化碳生成甲酸的催化循环机理, 催化循环的关键中间体可能是TpRu(PPh3)(ROH)H. 该中间体能同时转移负氢及醇配体中的氢质子到接近的二氧化碳分子上生成甲酸, 并吸收H2生成过渡态TpRu(PPh3)(OR)(H2). 该过渡态经过σ-复分解反应重新生成TpRu(PPh3)(ROH)H完成催化循环.  相似文献   

11.
标题化合物是在反应物摩尔比为V2O5∶H3PO4∶H2NCH2CH2NH2∶H2O=0.55∶4∶3.6∶265时, 175 ℃水热反应5 d合成的. 其结构特点是: 钒八面体[VO5N]共用角顶的氧形成“之”字型链, 链间由[PO4]共角顶连接成层; 乙二胺分子的一个N直接与V配位, 并伸向层间. 相邻层间存在强氢键. 晶体学数据: 单斜晶系, P21/c (No. 14), a=0.92108(2) nm, b=0.72851(1) nm, c=0.98204(2) nm, β=101.269(7)°, V=0.6462(4) nm3, Z=4, Dc=2.303 g•cm-3, R1=0.0417, wR2=0.0999.  相似文献   

12.
IntroductionSulfide-based open-framework materials are in-triguing compounds.They possess very diverse and in-teresting structures,and exhibit potential applicationsas a newgeneration of molecular sieves with the proper-ties of semiconductor materials[1].…  相似文献   

13.
From the kinetic studies of CCl3CH2CH2Br addition to 1-hexene, the rate constant of addition of the CCl3CH2CH 2 . ( e 1 R) radical to 1-hexene [1g e 1 kh=(5.2±0.1)–(13 000±800)/RT] has been determined. From the cotelomerization data, rate constants of the interaction of e 1 R-radical with ethylene [1g e 1 ke=(6.1±0.2)–(21 400±1 200)/RT] and carbon tetrachloride [1g e 1 kt=(7.5±0.2)–(37 000±1 200)/RT] have been calculated.
CCl3CH2CH2Br 1-. CCl3CH2CH 2 . - e 1 R.)- 1- (1g 1 K=(5,2±0,1)–(13 000±800)/RT), 1- , 1 R- (1g 1 K=(6,1±0,2)–(21 400±1200/RT) CCl4 (1g 1 K=(7,5±0,2–(37 000±1 200)/RT).
  相似文献   

14.
Variable temperature 119mSn Mössbauer data are presented for two organotin compounds which each contain 4- and 5-coordinate tin sites. The absorption line areas of each site have been determined and the Debye model of solids has been used to fit the experimental data. The Debye temperature associated with each site has been determined, and compared with other data.  相似文献   

15.
A novel organically templated vanadium tellurite (NH3CH2CH2NH3)2V2Te6O18 (1) has been hydrothermally synthesized and characterized by elemental analyses, IR, thermal stability analysis, magnetic susceptibilities and single crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic system, space group P21/n, , , , β=94.789(4)°, , Z=2, R1[I>2σ(I)]=0.0187, wR2[I>2σ(I)]=0.0482. Compound 1 exhibits a novel three-dimensional (3D) vanadium tellurite anion framework composed of vanadium, tellurium, and oxygen atoms through covalent bonds, with the [NH3CH2CH2NH3]2+ cations residing in the channels.  相似文献   

16.
17.
Cyclodiphosphazanes having donor functionalities such as cis-[tBuNP(OR)]2 (R = C6H4OMe-o (2); R = CH2CH2OMe (3); R = CH2CH2SMe (4); R = CH2CH2NMe2 (5)) were obtained in good yield by reacting cis-[tBuNPCl]2 (1) with corresponding nucleophiles. The reactions of 2-5 with [RuCl26-cymene)]2, [MCl(COD)]2 (M = Rh, Ir), [PdCl2(PEt3)]2 and [MCl2(COD)] (M=Pd, Pt) result in the formation of exclusively monocoordinated mononuclear complexes of the type cis-[{tBuNP(OR)}2MLn-κP] irrespective of the reaction stoichiometry and the reaction conditions. In contrast, 2-5 react with [RhCl(CO)2]2, [PdCl(η3-C3H5)]2, CuX (X=Cl, Br, I) to give homobinuclear complexes. Interestingly, CuX produces both mono and binuclear complexes depending on the stoichiometry of the reactants and the reaction conditions. The mononuclear complexes on treatment with appropriate metal reagents furnish heterometallic complexes.  相似文献   

18.
The novel, 1D semiconductor (H2NC4H8NCH2CH2NH2)(HNCH2CH2NH2)3Zn2Ge2Se8 has been synthesized under solvothermal conditions using N-(2-aminoethyl)piperazine as solvent and templating agent at 200 °C. The material was characterized by single crystal and powder X-ray diffraction, IR and Raman spectroscopy and thermogravimetric analysis. The compound consists of 1D anionic [Zn2Ge2Se8]4− chains made of alternating edge-shared [ZnSe4] and [GeSe4] tetrahedra that charged balanced by one N-(2-aminoethyl)piperazinium and three piperazinium cations. The optical properties were investigated with solid state UV–Vis/near IR spectroscopy and the results show that the solid is a medium gap semiconductor with an absorption edge at 1.8 eV.  相似文献   

19.
0引言 钼磷酸盐由于具有丰富的晶体结构特点和化学特性使得这种材料在催化、离子交换剂和材料科学等领域有着更加广阔的应用前景[1~3].  相似文献   

20.
[Rh(PhCOCHCOCH2CH2CH3)(CO)2] is characterised by crystallographic and density functional theory computational methods. The experimental structure is compared to the calculated structure, as well as to the structurally similar compound [Rh(PhCOCHCOCH2CH3)(CO)2] using root-mean-square calculations and a half-normal probability plot analyses.  相似文献   

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