Bridging complexes of rare earth and cobalt cluster as catalyst precursors for Fischer-Tropsch synthesis

Three new bridging complexes of rare earth and cobalt cluster were synthesized and characterized via ICP, IR and TG techniques. The structure of the complexes was speculated as： two rare earth atoms were bridged with four CF3COO–, and rare earth atoms were coordinated with cobalt carbonyl clusters to form a steady structure. Application of the complexes as the catalyst precursors was explored for Fischer-Tropsch synthesis. The study showed that the bridging complexes of rare earth and cobalt cluster had large molecular size and were difficult to enter pore path of γ-Al2O3, so they were dispersed on the surface of γ-Al2O3 support. In addition, the performance of Co（Ce）/ γ-Al2O3 was the best among the catalysts with complex as precursor and maintained 77.7% CO conversion at 220 oC for 80 operation hours.

The Assembly and Molecular Structure of a Novel One-dimensionalCyanide-bridged [Ni(pn)_2Ni(CN)_4]_n·nH_2 O Complex

The synthesis, structure and characterization of a new one-dimensional cyanide-bridgedcomplex [Ni(pn)_2Ni(CN)4]n'nH2O (where pn = 1,2-diaminopropane) are described. The structure ofthis complex consists of a one-dimensional polymeric chain-Ni(pn)2-NC-Ni(CN)2-CN-Ni(pn)2- inwhich the Ni(II) centers are linked by two CN groups.

TRIPLY BRIDGED BINUCLEAR COMPLEX OF OXOMOLYBDENUM(Ⅴ)WITH MERCAPTOPHENOLATE LIGANDS

Reaction of(n-Bu_4N)_xNa_(4-x)[a-Mo_8O_(26)](x=1-4)and mpH_2(mpH_2=o-mercaptophenol) leads to the formation of compound(n-Bu_4N)[Mo_2O_3(mp)_3Na(EtOH)_2(MeOH)],It crystallizes in the space group P2_1/n with four molecules per unit cell.The cell dimension is a=12.776(3),b=14.154(5),c=26.281(7)(?)=95.50(2)°,V=4730.5 (?),d_c=1.407 g/cm^3.Full-matrix refinement of 496 parameters on 3348 reflection data gave final R(R_w) value of 0.072(0.072).The two oxomolybdenum-mercaptophenolate,units are triply bridged by an inorganic oxygen atom and a doubly bridging mp^(2-)ligand.

SYNTHESIS AND STRUCTURE OF A NOVEL INFINITE-LAYER COPPER(Ⅱ)COMPLEX BRIDGED BY OXAMIDE AND PYRIMIDINE

The complex polymer[Cu_2(oxap)(pyr)_2]_n(ClO_4)_(2n),where oxap^(2-)stands for N,N' -bis(2—aminopropyl)oxamide,have been synthesized.It crystallizes in monoclinic system, space group P2_1/C,with a=8.721(2),b=8.679(2),c=16.741(2),β=98.59(0),Z=4.The least-square refinement coverged at R=0.054,R_w=0.055 with 1869 unique reflections.The whole structure of the complcx consists of layers of two-dimensional network arraying along a-axis with perchlorate ions interspersed in the gap between layers.Inside the layer. trans-oxamide-bridged copper(Ⅱ)dimers connected by pyrimidine in an asymmetric fashion spread out along be plane to form an infinite two-dimensional network.

SYNTHESIS AND CRYSTAL STRUCTURE OF THE FIRST THREE DIMENSIONAL NETWORK CU(Ⅱ) COMPLEX BRIDGED BY BOTH OXAMIDE AND AZIDE

A novel three dimensional network complex polymer [Cu_4(oxen)_2(N_3)_3]_n(ClO_4)_n·2nH_2O, where oxen is N,N' -bis(2-aminoethyl)oxamide dianion, has been synthesized. It crystallizes in triclinic system, space group P, with a=11.486(2), b=11.706(3), c=12.291(3) , α=77.42(2), β=67.59(2), γ=77.96(2)°, and z=2. The least-square refinements converged at R=0.047, with 3416 observed unique reflections. The complex has a pronounced three-dimensional character and can be viewed as the tetranuclear asymmetric repeating units through inversion and translation operations to extend a three-dimensional network. The structure of Cu_4 asymmetric unit consists of two square planar and two square pyramidal Cu central atoms linked by both azide ligands in end-on and end-to-end bonding modes, and oxamidate bridge in trans conformation.

Synthesis and Crystal Structure of Mercury BridgedBiferrocene Trinuclear Complex Hg(FcL)_2,Bis(S-methyl-N-(1-ferrocenyl-1-methyl)methylenedithiocarbazate)mercury(Ⅱ)

The title complex, mercury bridged biferrocene trinuclear complex Hg(FcL)2. Bis (S-methyl-N- (1-ferrocenyl-1-methyl) methylenedithiocarbazate) mercury,Crystallizes in space group Pbca with a =19. 510 (4), b=19. 921 (5), c=15. 581 (3)A. V=6095(3) A, Z=8,M.=863. 12, Dc=1.881 g/cm3; u=19. 24 cm-1 and F(000) = 3376. The final refinement of 2455 observed reflections is converged with R= 0. 043 and Rw=0.047. X-ray crystal structure analysis revealed that the coordinationgeometry of Hg atom is a distorted tetrahedron with two Hg-N bonds and two Hg- S bonds. The Schiff-base ligand loses a proton from its tautomeric thiol form and is cryordianted to the Hg aotm uia the mercapto sulphur and the β-nitrogen atoms.

二炔基桥联双核钌配合物的电喷雾质谱研究

A rapid method is applied to analyze conjugated organic ligands bridged binuclear ruthenium complexes by electrospray ionization-tandem mass spectrometry (ESI MSn).Fragmentation pattern be discussed.

Synthesis,Characterization and Crystal Structure of〔Co_2Mo_2(μ-_4-C_2HPh)(μ-CO)_4(CO)_4(η^-5C_5H_4C(O)Me)_2〕

The reaction of μ alkyne bridged dimolybdenum compound 〔Mo 2( μ C 2HPh)(CO) 4( η 5 C 5H 4C(O)Me) 2〕 1 with Co 2(CO) 8 in refluxing toluene gave a new butterfly compound 〔Co 2Mo 2( μ 4 C 2HPh)( μ CO) 4(CO) 4( η 5 C 5H 4C(O)Me) 2〕 2 which was fully characterized by elemental analysis, IR, 1H NMR and X ray single crystal diffraction techniques. 2 crystallized in monoclinic system, C 30 H 20 Co 2Mo 2O 10 , M r =850.23, space group P2 1/a(#14), a=14.165(5), b=12.498(2), c=16.204(2) , β = 96 50(2)°, V = 2850(1) 3, Z = 4, D c = 1.981 g cm -3 , F(000)=1672, μ (Mo Kα )=20.41 cm -1 , final R=0.030, R w =0.039 for 4831 observable reflections with I>2σ(I ). The structure contains a Co 2Mo 2 butterfly core, and each Mo-Co bond is spanned by an asymmetric semi bridging carbonyl ligand.

Synethesis and Crystal Structure of Bi(ethylenediamine)copper Tetracyanonickelate(II)

The crystal structure of the title compound C 8H 16 CuN 8Ni has been determined by single crystal X ray diffraction. The crystal is triclinic with space group P1, a=6.494(3), b=7.270(4), c=7.936(5) , α=106.67(3), β=91.33(4), γ=106.80(6)°, V=341.3(3) 3, Z=1, M r=346.54, F(000)=177, μ =2\^933mm -1 , D c =1.686 Mg/m 3. The final R factor is 0.0603 for 1214 unique observed reflections 〔 I≥2σ(I) 〕. The structure consists of 〔Cu(en) 2〕 2+ (en=ethylenediamine) cations and 〔Ni(CN) 4〕 2- anions linked together by two of the CN groups (the remaining two act as unidentate ligands) to form infinite chains, in the chain, the hydrogen bonds of N(4)…H-N(5) exist,with distance 3.148 , at the same time the hydrogen bonds of N(4)…H-N(7a) and N(5)-H…N(1a) (a: x-1,y-1,z-1 ) between the interchains also exist, with distances of 3.160 and 3.124 , so it forms a three\|dimensional structure of the title compound.

Synthesis and Crystal Structure of Compound [Ni(bipy)_3][(μ-oxo)Fe_2Cl_6]

The title compound [Ni(bipy)3][(-oxo)Fe2Cl6] (bipy = 2, 2?bispyridine) was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in monoclinic, space group P2l/c with unit cell parameters: a = 9.7085(7),b = 26.409(2), c = 14.014(1) ,?= 100.237(3), V = 3535.9(2) 3,Z = 4,C30H24Cl6Fe2N6NiO,Mr = 867.66, Dc = 1.630 g/cm3,F(000) = 1744, (MoK? = 1.824 mm-1, the final R = 0.0394 and wR = 0.0475 for 2750 observed reflections with I ≥ 2(I). The title compound contains cation of [Ni(bipy)3]2+ and anion of [(-oxo)Fe2Cl6] 2- which consists of two [FeCl3] fragments connected by an oxo bridge with the bond distances of Fe(2)O(1) 1.752(2) and Fe(1)O(1) 1.763(2) , and the bond angle of Fe(2)O(1)Fe(1) 148.6(2)? In the [Fe2(-oxo)Cl6]2- complex, the two iron(Ⅲ) centers exhibit a tetrahedral coordination with the distorted tetrahedron formed by three Cl atoms and one oxo bridge.

STUDY ON THE STRUCTURE AND SPECTRA OF BINUCLEAR BRIDGED COMPLEX μ-4,4-bipy [VO(acac)_2]_2

The synthesis and 1H NMR, ESR, IR, UV spectra of binuclear bridged complex μ-4,4-bipy[VO-（acac）2]2 are reported in this paper. The structure of the complex is discussed using measured spectral parameters.It is deemed that 4,4-bipy as a bridge passing through its two N atoms combined respectively with two V atoms at its sixth position, forming a binuclear bridged complex.The spectra are explained satisfactorily and coefficients of molecular orbitals,β1,β2 and 8m,are calculated from the results of ESR and UV etc.

Four Complexes of Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ)and Cu(Ⅱ)Based on 2-Morpholine-4-yl-4,6-di-pyrazol-1-yl-1,3,5-triazine

Three azide bridged complexes,namely,[Mn_(2)L_(2)(N_(3))_(4)(H_(2)O)_(2)](1),[Co_(2)L_(2)(N_(3))_(4)]·(H_(2)O)_(3)(2)and[Ni_(2)L_(2)(N_(3))_(3)(H_(2)O)]N_(3)·(H_(2)O)4(3)(L=2-morpholine-4-yl-4,6-di-pyrazol-1-yl-1,3,5-triazine),were synthesized by the reaction of L ligand,sodium azide with Mn(Ⅱ),Co(Ⅱ)and Ni(Ⅱ)chlorides.The copper(Ⅱ)chloride combined with thiocyanate and L ligand to form a mononuclear complex[CuL(CH3OH)(SCN)(NCS)](4).Complexes 1~4 were characterized by IR,elemental analysis and X-ray crystallographic analysis.It was worth noting that two Mn(Ⅱ)atoms were connected by the end-to-end mode in 1,while Co(Ⅱ)and Ni(Ⅱ)atoms were connected by the end-on mode in 2 and 3.In complex 4,the central copper atom was coordinated with a sulfur atom and a nitrogen atom of the two thiocyanate ligands,respectively.Hydrogen bonds,π-πstacking interactions,thermogravimetric analysis and fluorescence properties of 1~4 were studied.

Multiple damage detection in complex bridges based on strain energy extracted from single point measurement

Strain Energy of the structure can be changed with the damage at the damage location.The accurate detection of the damage location using this index in a force system is dependent on the degree of accuracy in determining the structure deformation function before and after damage.The use of modal-based methods to identify damage in complex bridges is always associated with problems due to the need to consider the effects of higher modes and the adverse effct of operational conditions on the extraction of structural modal parameters.In this paper,the deformation of the structure was determined by the concept of influence line using the Betti-Maxwell theory.Then two damage detection indicators were developed based on strain energy variations.These indices were presented separately for bending and torsion changes.Finite element analysis of a five-span concrete curved bridge was done to validate the stated methods.Damage was simulated by decreasing stiffness at different sections of the deck.The response regarding displacement ofa point on the deck was measured along each span by passing a moving load on the bridge at very low speeds.Indicators of the strain energy extracted from displacement influence line and the strain energy extracted from the rotational displacement influence line(SERIL)were calculated for the studied bridge.The results show that the proposed methods have well identified the location of the damage by significantly reducing the number of sensors required to record the response.Also,the location of symmetric damages is detected with high resolution using SERIL.

Molecular structure of imidazolate bridged binuclear zinc complex and its single crystal ESR spectra doped with bridged Cu—Zn complex

The X-ray crystal structure of [(dtma)ZnImZn(dtma)]ClO_4·2.5H_2O (Hdtma=4-Diethyl- enetriamineacetic acid) was determined.The crystal is of orthorhombic,space group Pbcn with a- 14.104(5),b=14.897(5),c=25.384(9),and Z=8.The least-square refinement of the structure leads to conventional R factor of 0.066.The magnetic properties of [(dtma)CulmZn(dtma)]CIO_4·2.5H_2O were investigated.From the single crystal ESR spectra of Zn—Im—Zn dimer doped with Cu—Im—Zn complex,the anisotropic g and A tensors and electronic spin-density of the Cu—Zn complex are obtained and the bonding nature of Cu is discussed.

Synthesis,structure and properties of an imidazolate bridged copper,zinc binuclear complex

A new imidazolate bridged Cu^(2+),Zn^(2+)binuclear complex[(dtma) CulmZn (dtma)]ClO_4· 2.5H_2O taken as active site model for Cu,Zn-SOD has been synthesized and its crystal structure determined.All the bond lengths, bond angles and the distance between Cu and Zn atoms in Cu-Im- Zn core of the model complex are close to those in Cu,Zn-SOD.ESR parameters of the model complex as a function of pH show that the imidazolate bridge is stable in pH range 10—12,and is broken on Zn side at pH～9.With decreasing pH,the imidazole is released at pH～4 and the dtma ligand dissociates from the Cu containing fragment at pH～2.4.

The bond evolution mechanism of covalent sulfurized carbon during electrochemical sodium storage process

The excellent energy storage performance of covalent sulfur-carbon material has gradually attracted great interest. However, in the electrochemical sodium storage process, the bond evolution mechanism remains an elusive topic. Herein, we develop a one-step annealing strategy to achieve a high covalent sulfur-carbon bridged hybrid(HCSC)utilizing phenylphosphinic acid as the carbon-source/catalyst and sodium sulfate as the sulfur-precursor/salt template, in which the sulfur mainly exists in the forms of C–S–C and C–S–S–C. Notably, most of the bridge bonds are electrochemically cleaved when the cycling voltage is lower than0.6 V versus Na/Na+, leading to the appearance of two visible redox peaks in the following cyclic voltammogram(CV) tests.The in-situ and ex-situ characterizations demonstrate that S^2- is formed in the reduction process and the carbon skeleton is concomitantly and irreversibly isomerized. Thus, the cleaved sulfur and isomerized carbon could jointly contribute to the sodium storage in 0.01–3.0 V. In a Na-S battery system, the activated HCSC in cut off voltage window of 0.6–2.8 V achieves a high reversible capacity(770 mA h g^-1 at 300 mA g^-1). This insight reveals the charge storage mechanism of sulfur-carbon bridged hybrid and provides an improved enlightenment on the interfacial chemistry of electrode materials.