Synthesis and Crystal Structure of Binuclear Copper （Ⅱ） Complex Containing （Dimethylaminomethyl）ferrocene

1 INTRODUCTION Transition metal complexes with ferrocene are of considerable interest in the past fifty years because of their novel structures and special properties[1, 2]. The chemistry of ferrocene and its derivatives has become richer and richer in the last decade. Many complexes containing ferrocenyl have been synthesized and characterized[3～5]. Recently we have reported the synthesis and crystal structure of dibromo[1,1?bis(diphenylphosphino)- ferrocene]cadmium (Ⅱ)[6]. Herein we…     

Synthesis and Characterization of a 1-D Zigzag Catenarian Compound [Sn（edt）2（p-phenylenediamine）]n

1 INTRODUCTION In recent years, the researches on tin sulfide ma- terials have drawn increasing attention of chemists owning to their potential applications as photo-vol- taic materials, holographic recording system[1, 2], so- lar control devices[3] and semiconductor materials. In the last decades, many finite adducts of tin (IV) thio- lates with organic amine ligands have been synthe- sized by self-assembly, such as cis-Sn(SPh)4(2,2?-bi- py)[4], cis-Sn(edt)2(ethyldimiane)[5], trans-Sn(…     

Synthesis and Crystal Structure of a Zinc(II) Complex Salt with the Schiff Base of Picolinaldehyde N-oxide and Semicarbazone

1 INTRODUCTION The donor properties of pyridine N-oxide and its substituted derivatives to form metal complexes have been widely investigated[1～3]. The resulting comple- xes were used as drugs[4] and catalysts[5]. So far, there have been a few reports on the synthesis of Schiff base derived from picolinaldehyde N-oxide with se- micarbazone (PNOS Scheme 1) and its metal com- plexes. And crystal structures of the complexes of PNOS with Au(III)[6], Pd(II)[7] and Cu(II)[8] were re- …     

A Periodic Density Functional Study on Adsorption Properties of Methoxy on Au（111） Surface

1INTRODUCTION Methoxy(CH3O)has been identified as the first intermediate in the decomposition of methanol on extensive list of clean transition metal surfaces,such as Ni(100)[1],Cu(100)[2,3],Cu(111)[4],Ag(111)[5],Au(110)[6],Pd(111)[7]and Ru(0001)[8].The electronic structure of the metal is a determining factor in OH bond scission.In fact,group IB clean surfaces have shown very low activity towards this reaction,al-though there are reports on low amounts of methoxy formed on clean Cu(…     

Theoretical Study of the Molecular and Electronic Structures of CPDT-TCNQ and Its Difluoro and Dimethyl Derivatives

1 INTRODUCTION Since the discovery of one-dimensional metallic behavior of tetrathiafulvalene (TTF) with tetracyano- quinodimethane (TCNQ)[1], organic charge-transfer (CT) complexes and CT salts have been intensively studied in search of electrically conducting and superconducting properties[2 ～ 6] which are most unusual for an organic material. The most intriguing property is that it is excellent metal with conducti- vity similar to that of metals at room temperature[7, 8]. In these…     

Stability of Fullerene Cages： C30 to C70 and Their Dependence on Shared Pentagon Bonds

1 INTRODUCTION Since the discovery of buckministerfullerene (C60)[1], experimental and theoretical studies of the structure and properties of fullerenes have spread worldwide. Many experimental studies appeared on their syntheses[2], isolation[3], and characterization[4]. Theoretically, except studies on their chemical pro- perties[5], most of the work was concentrated on their interesting geometric[6～8] and electronic structures[9, 10]. For example, the ground state of C48 has C2 symme…     

SYNTHESIS, SPECTRAL AND MAGNETIC CHARACTERISATION OF SOME BIMETALLIC ALKOXIDES OF NICKEL(Ⅱ)WITH GALLIUM(Ⅲ)AND ZIRCONIUM(IV)

Some interesting bimetallic isopropoxides of nickel(Ⅱ) with gallium(Ⅲ) and zirconium(Ⅳ), Ni[Ga(OPr~1)_4]_2 and Ni[Zr_2(OPr_1)_9]_2 have been synthesized by the interaction of NiCl_2·2Pr~1OH with K[Ga(OPr~1)_4],and K[Zr_2(OPr~1)_9] respectively, in 1:2 molar ratio. These bimetallic isopropoxides undergo facile alcohol interchange reactions with primary alcohols. However, reactions with tertiary alcohols result in the isolation of partially substituted derivatives with the compositions, Ni[Ga(OPr~1)(OBu~t)_3]_2 and Ni[Zr_2(OPr~1)_3(OBu~t)_6]_2. Characterisation of these derivatives has been made on the basis of elemental analyses, infrared, electronic spectral and magnetic susceptibility measurements. These studies suggest an octahedral geometry for nickel(Ⅱ) in the primary bimetallic alkoxides, while in the case of secondary and tertiary derivatives, an equilibrium is suggested between octahedral and tetrahedral forms.##属性不符     

Crystal Structure of Ethoxyethyl 3-(2-Chloro-5-pyridyl methylamino)-2-cyano-4-methylpent-2-enoate

1 INTRODUCTION The nature and topography of the herbicide binding site in the reaction center of photosystem Ⅱ (PSⅡ) have been the subject of intense interest for many years. Among several commercially important herbicides with different structures such as atrazine and polypeptide of the PSII reaction center[1], the cyanoacrylates with general structure 1 have proved hightly potent and useful as probes[2, 3] of the receptor because their activities as inhibitors of photosynthetic ele…     

Synthesis,Crystal Structure of Cis—dioxo—catecholatotungsten（VI） Complex and Its NMR Studies on the Interaction with ATP

Cis-dioxo-catecholatotungsten(VI) complex anion[W^(VI)O2-(OC6H4O)2]^2- was obtained with discrete protonated ethylenediamine (NH2CH2CH2NH3)^ cations by the reaction of tetrabutyl ammonium decatungstate with catechol in the mixed solvent of CH3OH,CH3CN and ethylenediamine,and compared with its molybdenum anaogue [Mo^(V) O2(OC6H4O)2]^3- by crystal structure,UV,EPR,The results of the UV and EPR spectra show that tungsten is less redox active than molybdenum since the molybdenum is reduced from Mo(VI) to Mo(V) but tungsten stays in the original highest oxidized state Mo(VI) when they are crystallized from the solution above.It is worthy to note that [W^(VI)O2(OC6H4O)]^2- shows the same coordination structure as its molybdenum analogue in which the metal center exhibits distorted octahedral coordination geometry with two cis-dioxocatecholate ligands and might have the related coordination structure feature with the cofactor of flavoenzyme because [Mo^(V)O2(OC6H4O)2]^3- presented essentially the same EPR spectra as flavoenzyme.The NMR studies on the interaction of the title complex with ATP reveal that the reduction of W(VI) to W(V) occurs when the title complex is dissolved in D2O and the W(V) is oxidized again when ATP solution is mixed with original solution and the hydrolysis of the catecholato ligand take places at mean time being monitored by ^1H NMR and ^13C NMR spectra.     

Syntheses,Structures, and Properties of Three Coordiantion Polymers： [Cd2（bpp）1.5（Hbpp）（phen）2]n, [Mn3（Htptc）2（phen）2（H2O）2]n,and {[Cu（btc）0.5（1,4-bib）]？2H2O}nSyntheses,Structures, and Properties of Three Coordiantion Polymers： [Cd2（bpp）1.5（Hbpp）（phen）2]n, [Mn3（Htptc）2（phen）2（H2O）2]n,and {[Cu（btc）0.5（1,4-bib）]？2H2O}n

Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers： [Cd2（bpp）1.5（Hbpp）（phen）2]n （1）, [Mn3（Htptc）2（phen）2（H2O）2]n （2）, and {[Cu（btc）0.5（1,4- bib）]·2H2O}n（3） （H2bpp = 2,6-bis（4＇-carboxyphenyl）-4-phenylpyridine, H4tptc = terphenyl-2,5,2＇,5＇-tetracar- boxylic acid, H4btc =biphenyl-2,2＇,4,4＇-tetracarboxylic acid, phen =1,10-phenanthroline, and 1,4-bib = 1,4-bis（1H-imidazol-1-yl）benzene）. Their structures have been determined by single- crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction （PXRD） analyses. In compound 1, the CdII cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D （3,4,5）-connected framework with the Point Schl？fli symbol of （42.6）2（43.62.8）（45.64.8）2. Compound 3 shows an unprecedented 3D （4,4）-connected framework with the Point Schl？fli symbol of （64.82）2（65.8）. Moreover, the luminescent property of 1 has been investigated.     

X@(HAINH)_(12)和X(HAINH)_(12)(X=F~-,Cl~-,Br~-,O~(2-),S~(2-),Se~(2-))复合物的结构和稳定性

用DFT的B3LYP方法在6-31G(d)基组的水平上,对闭式多面体簇合物(HA1NH)12及其内含式X@(HA1NH)12外接式X(HA1NH)12(X=F-,Cl-,Br-,O2-,S2-,Se2-)复合物的结构进行了构型优化和能量计算,并讨论了几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系,最后得到复合物结构的稳定性信息,具有Th对称性的X@(HA1NH)12(X=F-,Cl-,Br-,S2-,Se2-)复合物和具有C3对称性的O2-@(HA1NH)12复合物为内含式的基态结构,从能量角度分析,内含式复合物比外接式复合物的结构稳定.     

内含式复合物X@(HAlNH)12 (X=Be,Mg, Ca,Zn, Al+, Ga+)的结构和稳定性

在研究闭式多面体(HAlNH)12簇合物几何构型及稳定性的基础上, 用DFT的B3LYP方法在6-31G(d)的水平上, 对其内含式复合物X@(HAlNH)12 (X= Be, Mg, Ca, Zn, Al+, Ga+)进行了构型优化和能量计算, 并讨论了稳定结构的几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系. 用Gaussian 03的QST3方法确定了客体X通过笼面6-元环的迁移过渡态(TS)结构, 并用IRC方法对所得TS结构进行了验证. 最后得到内含式复合物X@(HAlNH)12结构在热力学和动力学上的稳定性信息, 其中复合物Ga+@(HAlNH)12的结构相对最稳定.     

X@(HAlNH)12和X(HAlNH)12 (X＝F－, Cl－, Br－, O2－, S2－, Se2－)复合物的结构和稳定性

用DFT的B3LYP方法在6-31G(d)基组的水平上, 对闭式多面体簇合物(HAlNH)₁₂及其内含式X@(HAlNH)₁₂和外接式X(HAlNH)₁₂ (X＝F^－, Cl^－, Br^－, O^2－, S^2－, Se^2－)复合物的结构进行了构型优化和能量计算, 并讨论了几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系, 最后得到复合物结构的稳定性信息, 具有T_h对称性的X@(HAlNH)₁₂ (X＝F^－, Cl^－, Br^－, S^2－, Se^2－)复合物和具有C₃对称性的O^2－@(HAlNH)₁₂复合物为内含式的基态结构, 从能量角度分析, 内含式复合物比外接式复合物的结构稳定.     

Structure and stability of endohedral complexes <Superscript>4/2</Superscript>X@(HAlNH)<Subscript>2</Subscript> (X = N,P, As,C<Superscript>−</Superscript>, Si<Superscript>−</Superscript>)

The structures of a closo-hedral cluster (HAlNH)₁₂ and endohedral complexes ^4/2X@(HAlNH)₁₂ (X = N, P, As, C⁻, Si⁻) are studied by density functional theory (DFT) at the B3LYP/6-31G(d) level. The geometries, natural bond orbital (NBO), vibrational frequency (ν₁), energetic parameters, magnetic shielding constants (σ), and nucleus independent chemical shifts (NICSs) are discussed. It is found that all guest species are minima at the cage center. Inclusion energies (ΔE _inc) of all species are negative except those of ⁴N and ^4/2P. In all species, the endohedral quartet states (⁴X) are energetically less favorable than their doublet states (²X). The calculations predict that caged X states only donate <0.50 e to the cage and preserve their unencapsulated ground states.     

Structure and Stability of Endohedral Complexes X@（HBNH）12

Using quantum chemistry methods B3LYP/6-31＋＋G（d,p） to optimize endohedral complexes X@（HBNH）12 （X=Li^0/＋, Na^0/＋, K^0/＋, Be^0/2＋, Mg^0/2＋, Ca^0/2＋, H and He）, the geometries with the lowest energy were achieved. Inclusion energy, standard equilibrium constant, natural charge, spin density, ionization potentials, and HOMO-LUMO energy gap were also discussed. The calculation predicted that X=Na^0/＋, K^0/＋, Mg^0/2＋, Ca^0/2＋, H and He are nearly located at the center of （HBNH）12 cluster. Li^＋ lies in less than 0.021 nm departure from the center. Li and Be^0/2＋ dramatically deviate from the center. （HBNH）12 prefers to enclose Li^＋, Be^2＋, Mg^2＋, and Ca^2＋ in it than others. Moreover, M@（HBNH）12 （M=Li, Na, K） species are ＂superalkalis＂ in that they possess lower first ionization potentials than the Cs atom （3.9 eV）.     

硼氢及客体二十面体簇合物的结构和稳定性

在(n=0、－1、－2、－3、－4)簇合物几何构型及稳定性研究的基础上,进一步对它的各种内含式和外 接式二十面体簇合物(X@B12H122－和XB12H122－,X=H0/＋、Li0/＋、He、Ne、Be0/2＋、Na＋、Mg2＋)进行了优化和 计 算.发现在内含式结构X@ B12H122－中,当X=Li＋、Be2＋、Mg2＋时,构型较稳定;在外接式结构中, XB12H122－(C3v)结构比XB12H122－(C2v)的结构稳定.通过IRC计算,确定XB12H122－(C2v)是X与B12H122－作用生成产物XB12H122－(C3v)的一种过渡态.     

Structure and bonding in the aluminum radical species Al x NH(3), HAlNH(2), HAlNH(2) x NH(3), and Al(NH(2))(2) studied by means of matrix IR spectroscopy and quantum chemical calculations

Experimental matrix IR spectra in alliance with extensive quantum chemical calculations provide a framework for the detailed evaluation of the structures and electronic properties of the doublet species Al x NH(3), Al(NH(3))(2), HAlNH(2), HAlNH(2) x NH(3), and Al(NH(2))(2). These species were the products of the reaction of Al atoms with NH(3) in an Ar matrix. While the two species Al x NH(3) and HAlNH(2) were already sighted in previous experiments, the results described herein lead to the first identification and characterization of HAlNH(2) x NH(3) and Al(NH(2))(2), the products of the reaction of Al atoms with two NH(3) molecules. The results allow a detailed reaction scheme leading to all the product species to be established. The unpaired electron in each of the species Al x NH(3), Al(NH(3))(2), HAlNH(2), HAlNH(2) x NH(3), and Al(NH(2))(2) is located near the Al atom, but there is a significant degree of delocalization, especially in Al(NH(2))(2), due to pi bonding interactions. The consequences for the barrier to pyramidalization at the N-atom are discussed.     

Computational investigation of the weakly bound dimers HOX...SO(3) (X = F, Cl, Br)

The electronic structure and thermochemical stability of the HOX-SO(3) (X = F, Cl, Br) complexes is studied using second-order M?ller-Plesset perturbation theory (MP2). The calculated dissociation energies of the HOF-SO(3), HOCl-SO(3), and HOBr-SO(3) complexes are 5.43, 6.02, and 5.98 kcal mol(-1) at MP2/6-311++G(3df,3pd) level, respectively. Anharmonic OH stretching frequencies of the HOX (X = F, Cl, Br) moieties along with the frequency shifts upon complex formation are calculated at the MP2/6-311++G(2df,2p) level. AIM and NBO analyses were also performed. Theoretical data strongly encourage performing of matrix-isolation studies of the title complexes and their spectroscopic identification.     

Theoretical studies on vibrational spectra of mixed cyanide-halide complexes of platinum(IV) and palladium(IV)

The vibrational spectra of mixed cyanide-halide complexes, M(CN)4X 2 2- and M(CN)5X2- (M=Pt and Pd; X=F, Cl, Br and I), have been systematically investigated by ab initio RHF, B3LYP and MP2 methods with LanL2DZ and SDD basis sets. The calculated vibrational frequencies of platinum complexes are evaluated via comparison with the experimental values. In the infrared frequency region, the C--N stretching vibrational frequencies calculated at B3LYP level with two basis sets are in good agreement with the observed values with deviations, -16-4 cm(-1) for Pt(CN)4X 2 2- and -18 to -2 cm(-1) for Pt(CN)5X2-. However, in far-infrared region, the results obtained at RHF level are better than those calculated at B3LYP and MP2 levels. For RHF/SDD method, the deviations for Ptz.sbnd;X and Ptz.sbnd;C stretching vibrational frequencies are -14-1 and -12 to -2 cm(-1) in the complex Pt(CN)4X2 2-, -19 to -11 and -15-14 cm(-1) in the Pt(CN)5X2- complex, respectively. The vibrational frequencies of palladium(IV) and some platinum(IV) complexes that have not been experimentally reported are predicted.     

(HAINH)_n(n=1～6)簇的结构、红外光谱和热力学性质的研究

用自洽场理论(HF)和密度泛函理论(DET)的B3LYP方法,在6-31G~μ水平上研究了HAINH的低聚物(HAINH)_n(n=1～6)簇的几何构型、电子结构、红外光谱和化学热力学性质,并比较了(HAINH)_n和(CIAINH)_n两种低聚物对应结构中化学键强弱,分析了引起(AIN)_n骨架结构发生变化的原因.结果表明,(HAINH)_n簇的基态结构为C_8(n=1),D_(2h)(n=2),D_(3h)(n=3),T_d(n=4),C_s(n=5)和D_(3d)(n=6)对称点群.HAINH基态结构中,AI-N键是三重键.在D_(2h)(n=2)和D_(3h)(n=3)结构中,所有AI-N键均为二重键.在Td(n=4)和D_(3d)(n=6)中,AI-N键为正常单键,而在C_s(n=5)结构中含有三种AI-N键:单键、双键和混合键.振动频率计算表明,结构a～f均为基态稳定结构.热力学计算给出的稳定性顺序为:f>d>e>c>b>a.