The complex [Mn(bipy)3]·(ClO4)2 was synthesied and characterized by X-ray diffraction. X-ray diffraction result for the single crystal showed that the crystal belongs to triclinic, space group P1, a=0.8123(2),b=1.1024(2), c=1.8646(4)nm,α=102.30(3)°,β=91.00(3)°,γ=99.69(3)°,V=1.6056(6)nm3,Z=2,Dc=1.494g·cm-3. The thermal decomposition of [Mn(bipy)3](ClO4)2 occurred in a three steps pattern. The reaction mechanism of the first step decomposition was deduced as n(1-α)[-ln(1-α)](n-1)/n with the activation energy of 130kJ·mol-1. 相似文献
The title cluster compound [WS4Cu3Br(bipy)2] has been synthesized by the reaction of (NH4)2[WS4], CuBr and 2,2′-bipy in DMF solution. Single crystal X-ray diffraction data show that the compound has a nest-shaped structure. Nonlinear optical properties (NLO) of the cluster were investigated by a Z-scan technique with a pulsed laser at 532nm. The cluster exhibits the strong NLO absorption and a self-defocusing effect (effective non-linear absorption coefficient, α2eff=7.3×10-11mW-1; effective non-linear refractive index, n2eff=3.9×10-11esu) when measured in a 6.0×10-4mol·dm-3 DMF solution. CCDC： 200397. 相似文献
In the presence of NH4PF6, reaction of [PPh4][(η5-C5Me5)WS3Cu3Br(dppm)] with excess pyridine afforded red prismatic crystals, [(η5-C5Me5)WS3Cu3Br(Py)3(dppm)](PF6) (1). It was characterized by elemental analy-sis, IR, UV-vis and 1H NMR spectroscopy and X-ray diffraction. 1 crystallizes in an orthorhombic system with space group Pna21 and unit cell parameters a=2.1124(4)nm, b=1.8944(4)nm, c=1.3338(2)nm, V=5.3375(19)nm3, Z=4, Dc=1.807g·cm-3,Mr=1452.42, F(000)=2864, μ=4.342mm-1, R1=0.0487, wR2=0.1027. The structure of the cluster cation contains an incomplete cubane-like WS3Cu3 core where Cu(1) and Cu(2) atoms are bridged by a dppm ligand. Each of the three Cu atoms adopts a distorted tetrahedral coordi-nation geometry. The W-Cu(1), W-Cu(2) and W-Cu(3) distances are 0.27698(17)nm, 0.2772(17)nm, and 0.27065(9)nm, respectively. CCDC： 199845. 相似文献
Reaction of a preformed cluster [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 (1) in MeCN with LiCl and PPh3 gave rise to a tetranuclear cationic cluster [(η5-C5Me5)WS3{Cu(PPh3)}3Cl](PF6) (2). The title compound 2 was characterized by elementary analysis, IR, UV-Vis, 1H NMR, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P21/c with a=1.799 8(4) nm, b=2.083 6(4) nm, c=1.913 5(4) nm, β=113.63(3)°, V=6.574(3) nm3, Z=4. The cluster cation [(η5-C5Me5)WS3{Cu(PPh3)}3Cl]+ of 2 contains a strongly distorted, cubane-like structure [WS3Cu3Cl] in which one Cl weakly fills into the void of the nido-like [WS3Cu3] fragment with three relatively long Cu-Cl distances. CCDC: 270415. 相似文献
The thermal behaviors of clusters [Ag3WS3Br](PPh3)3 and [Cu3WS3Br](PPh3)3 (PPh3=triphenyl phosphine) in a nitrogen atmosphere were studied under the non-isothermal conditions by simultaneous TG-DTG-DSC and EDS techniques. The results showed that the evolution of PPh3 generally proceeded before the release of the other moiety in one or two step-mode. The mechanisms, the kinetic and the thermodynamic parameters for decomposition of PPh3 of both clusters were determined and calculated by jointly using several methods, which showed that its evolution was controlled by Avrami-Erofeev equation. The results also showed that there was no new stable phase composed of W-Ag(Cu)-S-Br after release of organic moiety PPh3 and that CVD method was not applicable to their further processing. 相似文献
Opening the cluster core : Substitution of the chloride ligand in the novel cationic cluster [W3CuS4H3Cl(dmpe)3]+ (see figure; dmpe=1,2‐bis(dimethylphosphino)ethane) by acetonitrile is promoted by water addition. Kinetic and density functional theory studies lead to a mechanistic proposal in which acetonitrile or water attack causes the opening of the cluster core with dissociation of one of the Cu? S bonds to accommodate the entering ligand.
The accuracy and scope of application of previously reported approximations of the temperature integral were evaluated. The exact solution was obtained independently by solving the temperature integral numerically be Simpson's rule, the trapezoidal rule and the Gaussian rule. Two new approximations have been proposed: $$\begin{gathered} P(X) = e^{ - x} (1/X^2 )(1 - 2/X)/(1 - 5.2/X^2 ) \hfill \\ P(X) = e^{ - x} (1/X^2 )(1 - 2/X)/(1 - 4.6/X^2 ) \hfill \\ \end{gathered} $$ whereX=E/RT. The first equation gives higher accuracy, with a deviation of less than 1% and 0.1% from the exact solution forX≥7 andX≥10, respectively. The second equation has a wider scope of application, with a deviation of less than 1% forX≥4 and of less than 0.1% forX≥35. 相似文献
The kinetics of reaction of the [W3PdS4H3(dmpe)3(CO)]+ hydride cluster ( 1 +) with HCl has been measured in dichloromethane, and a second‐order dependence with respect to the acid is found for the initial step. In the presence of added BF4? the second‐order dependence is maintained, but there is a deceleration that becomes more evident as the acid concentration increases. DFT calculations indicate that these results can be rationalized on the basis of the mechanism previously proposed for the same reaction of the closely related [W3S4H3(dmpe)3]+ cluster, which involves parallel first‐ and second‐order pathways in which the coordinated hydride interacts with one and two acid molecules, and ion pairing to BF4? hinders formation of dihydrogen bonded adducts able to evolve to the products of proton transfer. Additional DFT calculations are reported to understand the behavior of the cluster in neat acetonitrile and acetonitrile–water mixtures. The interaction of the HCl molecule with CH3CN is stronger than the W? H???HCl dihydrogen bond and so the reaction pathways operating in dichloromethane become inefficient, in agreement with the lack of reaction between 1 + and HCl in neat acetonitrile. However, the attacking species in acetonitrile–water mixtures is the solvated proton, and DFT calculations indicate that the reaction can then go through pathways involving solvent attack to the W centers, while still maintaining the coordinated hydride, which is made possible by the capability of the cluster to undergo structural changes in its core. 相似文献
