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粱映秋  赵文运  徐蔚清  张致贵 《化学学报》1985,43(12):1126-1130
本文测定了原子簇化合物[Mo2O2S2(S2)2][2-]的红外和拉曼光谱,并在乙腈溶液中测得其共振拉曼光谱和退偏振比。利用X光晶体结构数据,对此阴离子的伸缩振动作了简化的正则坐标分析计算。所得结果可以帮助分析和归属一些Mo-Fe-S原子簇化合物的振动光谱。  相似文献   

3.
Na2WO4·2H2O-H2O2催化氧化苯甲醛制备苯甲酸   总被引:4,自引:0,他引:4  
以30%H2O2为氧源,Na2WO4·2H2O催化氧化苯甲醛制备苯甲酸.考察了H2O2用量,反应时间,催化剂和酸性添加物(硫酸氢钠)对苯甲酸收率的影响和在非酸性环境下,表面活性剂对苯甲酸收率的影响.结果表明,加入非离子表面活性剂能有效的提高苯甲酸的收率,特别是添加β-环糊精,苯甲酸的收率达90.03%.  相似文献   

4.
2MgO·2B2O3·MgCl2·14H2O-MgCl2-H2O体系30℃相平衡   总被引:2,自引:0,他引:2  
用相平衡方法研究2MgO@2B2O3@MgCl2@14H2O在30℃不同质量分数MgCl2水溶液中的溶解转化产物及其溶解度.结果表明,该复盐在MgCl2的质量分数0~2%浓度范围,发生不同步溶解并转化为多水硼镁石(2MgO@3B2O3@15H2O);在MgCl2的质量分数2%~13.8%浓度范围,转化为柱硼镁石(MgO@B2O3@3H2O),这一结果比文献报导的该硼酸盐的形成温度低了13℃,为盐湖硼酸镁矿物柱硼镁石形成的解释提供了物理化学依据;而在MgCl2质量分数大于13.8%时,同步溶解,不发生转化.提出了溶解相转化反应机理.  相似文献   

5.
关于过渡金属Pd,Pt对C_2H_2的吸附和氢化实验研究前人已作了不少工作,但有关Pd,Pt与C_2H_2之间成键问题的理论研究还尚不多见。为了了解Pd,Pt d轨道对炔键的活化行为和成键特性,本文以MC_2H_2(M=Pd,Pt)为模型,用赝势计算方法,对Pd,Pt与C_2H_2键的相互作用进行了研究。一、计算方法由于重原子的内层轨道对形成分子贡献很小,内层电子的相对论效应极为严重。本文采用Ps—HONDO程序,选取Hay的有效核芯势和价轨道Gaussian基组,对重原子Pd和Pt进行了价电子从头计算,对C和H进行了全电子从头算.部分地消除重原子内层电子相对论效应所引起的误差。  相似文献   

6.
曾庆松  陈文凯  戴文新  李奕  丁开宁 《催化学报》2009,30(12):1209-1214
 采用密度泛函理论探讨了 TiO2 表面负载 Co2B2 和 Co2B2Pt 合金簇可能的负载构型. 结果表明, Co2B2 和 Co2B2Pt 合金簇倾向于以两个 Co 的形式负载在两个氧上. 态密度分析发现, 负载后, Co2B2 合金簇中部分 Co 原子和 B 原子成键加强, Co2B2Pt 合金簇中 Pt 原子和 B 原子成键也加强, 形成新的轨道. CO 和 O2 在 Co2B2/TiO2 和 Co2B2Pt/TiO2 表面吸附的结果表明, Co2B2Pt/TiO2 催化氧化 CO 性能的提高是由于 Pt 原子提高了 Co2B2 合金簇吸附 CO 和 O2 的能力.  相似文献   

7.
分别在MP2/3-21G!!、CCSD(T)/3-21G!!//MP2/3-21G!!和B3LYP/3-21G!!3种水平上,计算研究了气相反应Cl2 2HI=2HCl I2的机理,求得一系列四中心和三中心的过渡态.通过比较六种反应通道的活化能大小,得到了相同的结论:双分子基元反应Cl2 HI"HCl ICl和ICl HI"I2 HCl的最小活化能小于Cl2、HI和ICl的解离能,从理论上证明了反应Cl2 2HI=2HCl I2将优先以分子与分子作用形式分两步完成.用内禀反应坐标(IRC)验证了MP2/3-21G!!方法计算得到的过渡态.  相似文献   

8.
报道了五元体系K2+2, Mg2+∥Cl2-2,SO2-4-CO(NH2)2-H2O在脲不饱和区及其边界四元体系MgSO4-MgCl2-CO(NH2)2-H2O在25 ℃时的等温溶度研究结果, 绘制了体系等温溶度的盐分组成图、水量图以及饱和溶液的折光率-组成图. 五元体系在脲的参与下, 交互反应K2Cl2+MgSO4→K2SO4+MgCl2向有利于生成硫酸钾和软钾镁矾K2SO4*MgSO4*6H2O(pic.)的方向进行, 这两者的相区较无脲时明显增大.  相似文献   

9.
通过实验验证,指出了一些期刊涉及Na2O2吸收CO2和NO混合气体的规律性等文章的知识性错误,认为习题训练中应回避此类问题,或是以此问题对学生置疑,引导学生实验探究,进行批判性教学。  相似文献   

10.
CO加氢反应机理一直是许多化学工作者感兴趣的课题.Rh催化剂因其优良的性能而被用于 CO加氢机理研  相似文献   

11.
4,4'-联吡啶与二苄基二硫代氨基甲酸镉配合物[Cd(DBTC)2]2 (1)反应得到加合物[Cd(DBTC)2(4,4'-bipy)] (2) (DBTC=N,N-二苄基二硫代氨基甲酸), 通过晶体结构分析及红外光谱等研究其结构与性质. 结果表明: 引入小分子配体会破坏[Cd(DBTC)2]2 (1)的二聚结构, 加入吡啶则得到单核的吡啶加合物[Cd(DBTC)2py] (3), 而引入4,4'-联吡啶后其结构变为新型的一维链状结构的配位聚合物2, 这种结构在二硫代氨基甲酸金属配合物中少见报道. 也比较了不同配体如吡啶及4,4'-联吡啶对Cd(II)及Zn(II)配合物结构的影响.  相似文献   

12.
金琼花  徐立军  孙静静  代永成 《化学学报》2009,67(19):2193-2198
合成了3种新的超分子配合物[Cd(H2biim)(2,2'-bipy)(NO3)2] (1), [Cu(H2biim)(2,2'-bipy)(H2O)](NO3)2 (2)和[Zn(H2biim)(2,2'-bipy)(H2O)](NO3)2 (3) (H2biim=双咪唑; 2,2'-bipy=2,2'-联吡啶), 并通过X射线单晶衍射测定了其结构. 配合物1~3均为单斜晶系, 属于P2(1)/c空间群, 在1中, Cd(II)为六配位, 它与双咪唑的2个氮原子, 联吡啶的2个氮原子和2个硝酸根的2个氧原子配位. 在2和3中, Cu(II)和Zn(II)均为五配位的, 它们与双咪唑的2个氮原子、2,2'-联吡啶的两个氮原子和一个水分子配位. 1~3的对称单元均通过双咪唑、硝酸根和水之间形成的氢键R21(7), R21(4) 和R44(18)构筑了1D链状超分子.  相似文献   

13.
A coordination polymer of [Cd{5-(NO2)sal}2(2,2'-bipy)]n (5-(NO2)sal=5-nitrosalicylate, 2,2'-bipy=2,2'-bipyridine) was synthesized by hydrothermal reaction and characterized by elemental analysis, IR and X-raydiffraction single crystal structure analysis. The title complex crystallizes in monoelinic with space group C2/c, a=2.730 8(16) nm, b=1.272 3(5) nm, c=0.674 5(3) nm,β=96.73(2)°, V=2.327(2) nm3, Z=4, R=0.022 2, wR=0.057.The 5-nitrosalicylate anions doubly bridge the Cd(Ⅱ) atoms to form one-dimensional polymeric chain with therepeated eight-membered ring units (Cd-O-C-O)2. The crystal structure is stabilized by intra- and interchainhydrogen bonds interactions.  相似文献   

14.
以对乙酰氨基苯甲酸和2,2′-联吡啶为配体合成了一个新配合物[Cd(C9H8O3N)2(2,2′-bipy)(H2O)]2·(H2O)3。该配合物晶体属三斜晶系,空间群P1,晶胞参数:a=1.2559(3)nm,b=1.5068(3)nm,c=1.6507(3)nm,α=112.14(3)°,β=101.83(3)°,γ=93.84(3)°,V=2.7959(10)nm3,Dc=1.592g·cm-3,Z=4,μ(MoKα)=0.840mm-1,F(000)=1364,最终偏离因子R1=0.0276,wR2=0.0683。标题配合物的不对称单元由2个独立的单核结构Cd(C9H8O3N)2(2,2′-bipy)(H2O)和3个晶格水分子组成。中心镉髤离子处于六配位的变形八面体环境中。本工作测定了配合物的荧光和电化学性能。  相似文献   

15.
李兵  郑寿添  杨国昱 《结构化学》2009,28(5):531-536
Two new hybrid polyoxotungstates, [Co(2,2'-bipy)3][a-H5PW11CoO40]-3H2O 1 and [Fe(2,2'-bipy)3]2[a-HBW12O40]-2.5H2O 2 (2,2'-bipy = 2,2'-dipyridyl), have been hydrothermally synthesized and characterized by IR, TGA and single-crystal X-ray structural analyses. The results of X-ray crystallography analyses exhibit that 1 consists of one a-Keggin anion [a-H5PW11CoO40]2- and one isolated [Co(2,2'-bipy)3]2+ complex, while 2 is constructed from one a-Keggin anion [a- HBW12O40]4- and two isolated [Fe(2,2'-bipy)3]2+ cations. The data for 1: orthorhombic system, space group Pbcn, a = 16.062(6), b = 27.278(10), c = 16.951(6)A, V = 7427(5)A3 and Z = 4; and those for 2: triclinic system, space group P1, a = 13.787(3), b = 17.857(5), c = 18.918(5)A, a = 88.009(12), β = 72.768(10), γ = 74.935(10)°, V = 4291(2)A3 and Z = 2.  相似文献   

16.
Hydrothermal reactions of 5-sulfoisophthalic acid (HO(3)SC(6)H(3)-1,3-(CO(2)H)(2), H(3)L) with M(II) carbonate (or oxide) and 4,4'-bipyridine (4,4'-bipy) (or 2,2'-bipyridine, 2,2'-bipy) resulted in three new metal carboxylate-sulfonate hybrids, namely, [CdL(H-4,4'-bipy)] (1) and [Cd(3)L(2)(2,2-bipy)(4)(H(2)O)(2)].2H(2)O (2) with layered structures and [ZnL(H-4,4'-bipy)(H(2)O)].2H(2)O (3), whose structure features a one-dimensional double chain. The cadmium(II) ion in complex 1 is seven-coordinated by five carboxylate oxygen atoms and one sulfonate oxygen atom from four ligands and a unidentate 4,4'-bipyridine. The interconnection of the cadmium(II) ions through bridging carboxylate-sulfonate ligands resulted in the formation of a <002> double layer with the bipyridyl rings orientated toward the interlayer space. Complex 2 has a different layered structure. Cd(1) is seven-coordinated by two bidentate chelating carboxylate groups from two ligands, a bidentate chelating 2,2'-bipy and an aqua ligand, and Cd(2) is octahedrally coordinated by two bidentate chelating 2,2'-bipy's, a sulfonate oxygen, and an aqua ligand. The coordination geometry around Cd(3) is similar to that of Cd(1) with the aqua ligand being replaced by an oxygen atom from the sulfonate group. The carboxylate-sulfonate ligand acts as pentadentate ligand, bridging with three cadmium(II) ions. The bridging of cadmium(II) ions through the carboxylate-sulfonate ligands resulted in the formation of <006> and <003> layers; the 2,2'-bipy molecules and [Cd(2)(2,2'-bipy)(2)(H(2)O)] cations are orientated to the interlayer space. Complex 3 features a 1D metal carboxylate-sulfonate double chain along the diagonal of the a- and b-axes. The zinc(II) ion is octahedrally coordinated by four carboxylate O atoms from three ligands, a unidentate 4,4'-bipy, and an aqua ligand. Each pair of zinc(II) ions is bridged by two carboxylate groups from two ligands to form a dimer, and such dimeric units are interconnected by bridging ligands to form a double chain. The sulfonate group of the carboxylate sulfonate ligand remains noncoordinated and forms a number of hydrogen bonds with aqua ligands as well as lattice water molecules.  相似文献   

17.
Fu ML  Guo GC  Liu X  Chen WT  Liu B  Huang JS 《Inorganic chemistry》2006,45(15):5793-5798
The incorporation of [Mn(2,2'-bipy)2]2+ with thioarsenate resulted in the formation of two novel compounds, [Mn3(2,2'-bipy)3(As(V)S4)2]n.nH2O (1) and Mn2(2,2'-bipy)As2(III)S5 (2), in which the main-group chalcogenide framework is incorporated with a [tm(2,2'-bipy)m]n+ complex. Meanwhile, the tetrathioarsenate(V) anion acts as a new mu3-1kappaS:1,2kappaS':2,3kappaS":3kappaS'" ligand in 1, in which all four S atoms of the [As(V)S4]3- anion are coordinating to metal. As a result, the two compounds exhibit semiconducting properties (Eg = 2.18 eV (1) and 1.83 eV (2)) and strong blue photoluminescence, with the emission maximum occurring at about 440 nm. Magnetic measurements show that both compounds have AF ordered states with Néel temperatures of 19 and 24 K for 1 and 2, respectively.  相似文献   

18.
配合物[Mn(2,2''-bipy)(H2O)4]·(m-phth)的水热合成和晶体结构   总被引:1,自引:1,他引:1  
A mononuclear manganese complex [Mn(2,2'-bipy)(H2O)4]·(m-phth) (2,2'-bipy=2,2'-bipyridine, m-phth=isophthalate) has been synthesized by hydrothermal methods. The crystal structure was determined by singlecrystal X-ray diffraction. The crystal is of orthorhombic, space group Pnna with a=0.766 8(8) nm, b =2.050 2(2)0.027 0, R=0.028 0 and wR=0.075 5. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 2,2'-bipyradine and four oxygen atoms from water molecules, completing an octahedral coordination geometry. The isophthalate molecules are included in the lattice and connected to Mn(2,2'-bipy)(H2O)4 by hydrogen bonding interactions to form a three-dimensional supramolecular structure. CCDC:286965.  相似文献   

19.
1 INTRODUCTION Polyoxometalates (POMs) are one of the most widely used inorganic components due to their at- tractive electronic and molecular properties with va- rious applications in catalysis, medicine, materials science[1~3] and so on. Exploration of transition me- tal complex cations as well as organic component which functions as ligand as building blocks in the construction of metal oxide composite materials is a fruitful strategy[4, 5]. Among the polyoxometalates studied to dat…  相似文献   

20.
水热合成法合成了新颖的三核超分子配合物[Cd3(PDA)3(2,2′-bipy)3(H2O)2].2H2O(1)(H2PDA=pyridine-2,6-dicarboxylic acid),并进行了元素分析、红外、热重、荧光及单晶衍射测试。该化合物属单斜晶系,P21/n空间群,晶胞参数分别为:a=2.12281(14)nm,b=1.006 09(7)nm,c=2.830 64(19)nm,β=108.937 0(10)°。中心原子配位数为7,羧基以双齿形式将Cd1、Cd2、Cd3桥联组成三核配合物。分子间氢键与π-π堆积构筑成三维超分子结构。荧光分析表明该配合物在室温下发出强烈的蓝色荧光,具有潜在的应用价值。  相似文献   

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