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1.
A novel complex Cu(PPh3)2(acac) 1 (PPh3 = triphenylphosphine, acac = acetylacetone) was obtained by a solution reaction and structurally characterized by X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 13.7361(8), b = 12.8204(7), c = 19.7638(13) , β = 95.946(2)°, C41H37CuO2P2, Mr = 687.19, V = 3461.7(4) 3, Z = 4, Dc = 1.319 g/cm3, S = 1.067, μ(MoKα) = 0.758 mm–1, F(000) = 1432, R = 0.0403 and wR = 0.0990. Complex 1 is characterized by an isolated structure. X-ray structure analysis of 1 shows that acac behaves as a chelating ligand and PPh3 coordinates as a monodentate ligand to the Cu(I) atoms. Photoluminescent investigation reveals that the title complex displays a strong green-light emission.  相似文献   

2.
Cyclic voltammetry and galvanostatic coulometry techniques were used to determine how the redox properties of osmium binuclear -oxocarboxylates [Os2 IV(-O)(-O2CR)2Cl4L2] (R = CH3, CCl3; L = PPh3 and R = CH3; L = AsPh3) are influenced by the nature of the bridging carboxylate ligand RCOO and ligand L. It was shown that all compounds in solution of dichloromethane undergo two single-electron reduction processes. The data obtained were compared with the DFT calculations of the electronic structure of the model complexes [Os2 IV(-O)(-O2CR)2Cl4L2] (R = CH3, CCl3; L = PH3 and R = CH3; L = AsH3).  相似文献   

3.
4.
Electrochemical studies of the newly synthesized bis(triphenyl phosphine) ruthenium(II) complex, cis-[RuCl2(L)(PPh3)2] (1, with L = 2-(2′-pyridyl)quinoxaline, C13N3H9), were performed in acetonitrile (ACN). For this purpose, cyclic voltammograms (CVs) as well as electrochemical impedance spectra (EIS) were recorded on either glassy carbon (GC), platinum (Pt), gold (Au), or multi-walled carbon nanotube (MWCNT) electrodes. Qualitative examination of solutions of 1 in ACN was performed on the basis of conductivity measurements and electrospray ionization mass spectrometry (ESI–MS). The conductivity data suggest that 1 is a 1 : 1 type electrolyte in ACN. The ESI spectra further demonstrate that upon dissolution of 1 in ACN progressive replacement of chloro- and PPh3-ligands by ACN occurs, leading to formation of [RuCl(L)(PPh3)(CH3CN)2]+Cl?, [2 + Cl ? ]. The CVs recorded for [2 + Cl ? ] on various working electrodes demonstrate that the reversibility of the redox couple 22 +/+ enhances with the order: Au < Pt < MWCNT < GC. The EI spectra verify that GC and MWCNT electrodes provide insignificant barrier for interfacial electron transfer since they afford less charge-transfer resistance.  相似文献   

5.
通过对铀采用相对赝势基组, 其它原子使用6-31+G(d)基组, 应用密度泛函理论(DFT)以及B3LYP方法对UO2+2离子与F-、CO2-3和NO-3的各配位结构进行优化和频率计算. 计算考虑了气相和水溶剂化两种状态, 其中溶剂化模型采用连续导体介质理论模型(CPCM). 计算结果显示配体的配位数与O=U=O对称伸缩振动频率存在线性关系. 配体在气相和水溶液中存在的关系基本符合通式: νs=-Agasn+983和νs=-Aaqn+821(Agas 和Aaq为常数, 表示每增加一个配体振动频率的变化值; n为配体配位数). 其中F-对应Agas=53 cm-1, Aaq=11 cm-1; CO2-3对应Agas=85 cm-1, Aaq=19 cm-1; NO-3对应Agas=48 cm-1, Aaq=-10 cm-1. 并且Aaq值与实验值一致.  相似文献   

6.
7.
Heteroligand complexes Ln(L)(iso-Bu2PS2)2(NO3) (Ln = Sm, Tb, Dy; L = Phen, 2,2??-Bipy) (I?CVI) are synthesized. The structure of Dy(Phen)(iso-Bu2PS2)2(NO3) (III) is determined from the data of X-ray structure analysis. The crystal structure of complex III is based on discrete mononuclear molecules in which the Dy atom has distorted dodecahedral coordination (polyhedron N2O2S4). The ligands Phen, iso-Bu2PS 2 ? and NO 3 ? are bidentate-cyclic. According to the X-ray diffraction analysis data, complexes I and II are isostructural to compound III. Complexes I?CVI have photoluminescence in the visible spectral range. The photoluminescence spectra of solid samples of compounds I?CVI exhibit bands corresponding to the radiative electron transitions of the Sm3+, Tb3+, and Dy3+ ions. Among the studied compounds I?CVI, the Tb(III) complexes are characterized by the most intense photoluminescence.  相似文献   

8.
The crystals of Ba2[Cu(Edtp)](ClO4)2 · 5H2O (i) contain the tetragonal-pyramidal complexes of Cu(II) with ethylenediaminetetra-3-propionate ion with one noncoordinated propionate group. The [Cu(Edtp)]2− complex ions and two sorts of the Ba atoms form two-dimensional supramolecular aggregate. Two Ba(1) atoms and one Cu atom form a tetramer by means of the coordinated carboxyl group and a free propionate group. The tetramers are united through the propionate group into ribbons, which are joined by the Ba(2) atoms into the layers. The coordination sphere of each B atom involves four water molecules, including two bridging water molecules. The perchlorate ions are also coordinated by the Ba atoms, one Ba atom acting as a bridge. The structure of the previously studied Ba2[Cu(Edta)](ClO4)2 · 6H2O (II) crystals with the hexadentate ethylenediaminetetraacetate ion is shown to be similar to that of complex I, but in the case of II, the Ba atoms are equivalent as regards the number of the complex anions bound to them. Original Russian Text ? M. Zabel, V.I. Pavlovskii, A.L. Poznyak, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 1, pp. 55–60.  相似文献   

9.
The synthesis, IR spectra, and the temperatures of the transition into a ferromagnetic state (T c) of layered ferromagnetics [R3RX[MCr(C2O4)3 (M = Mn, Fe, Co, Cu, and Ni) with the [Ph3BuP]+, [Bu3RN]+ (R = Pr, Et, and Me) cations capable of subsequently changing the distances between metallooxalate layers have been considered. The temperatureT c has been found to be independent of the size of the organic cation. It is believed that the determining factors in the transition to a ferromagnetic state are exchange interactions inside the metallooxalate layer.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2327–2330, September, 1996.  相似文献   

10.
Two new mixed metal cluster complexes PtRu3(CO)10(PPh3)(3-S)2,3 14% yield and PtRu3(CO)9(PPh3)2(3-S)2,4 23% yield were obtained from the reaction of Ru3(CO)9(3-S)2,1 with Pt(PPh3)2(C2H4) at 0°C. The cluster of4 consists of a spiked triangle of four metal atoms with two triply bridging sulfido ligands. The reaction of Ru4(CO)11(4-S)2,2 with Pt(PPh3)2(C2H4) yielded the expanded mixed-metal cluster complex PtRu4(CO)12(PPh3)(4-S)2,5 in 12% yield. The structure of the cluster5 can be described as a pentagonal bipyramid of five metal atoms and two sulfido ligands with one metal-metal bond missing. Compounds4 and5 were characterized by a single-crystal X-ray diffraction analyses.  相似文献   

11.
《Polyhedron》1999,18(26):3491-3495
The lead halide adducts Pb(L)I2 (L=2,2′-bipyridine, 1,10-phenanthroline) have been prepared and structurally characterized. Each lead atom adopts a distorted octahedral coordination and shares an edge to form one-dimensional polymer. There is π–π interaction between aromatic rings of the interchains in PbI2(phen), this stacking causes PbI2(phen) to be more stable than PbI2(bpy) in thermal behavior.  相似文献   

12.
In order to shed light upon the nature and mechanism of 4f-3d magnetic exchange interactions, a series of binuclear complexes of lanthanide(3+) and chromium(3+) with the general formula [Ln(L)5(H2O)2Cr(CN)6]·mL· nH2O (Ln=La (1), Ce (2), Pr (3), Nd (4); x=5, y=2, m=1 or 2, n=2 or 2.5; L=2-pyrrolidinone) and [Ln(L)4(H2O)3Cr(CN)6] ·nH2O (Ln=Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Er (10); x=4, y=3, m=0, n= 1.5 or 2.0; L=2-pyrrolidinone) were prepared and the X-ray crystal structures of complexes 2, 6 and 7 were determined. All the compounds consist of a Ln-CN-Cr unit, in which Ln^3+ in a square antiprism environment is bridged to an octahedral coordinated Cr^3+ ion through a cyano group. The magnetic properties of the complexes 3 and 6-10 show an overall antiferromagnetic behavior. The fitting to the experimental magnetic susceptibilities of 7 give g= 1.98, J=0.40 cm^-1, zJ'= -0.21 cm^-1 on the basis of a binuclear spin system (Scd=7/2, Scr=3/2), revealing an intra-molecular Gd^3+-Cr^3+ ferromagnetic interaction and an inter-molecular antiferromagnetic interaction. For 7 the calculation of quantum chemical density functional theory (DFT), combined with the broken symmetry approach, showed that the calculated spin coupling constant was 20.3 cm^-1, supporting the observation of weak ferromagnetic intra-molecular interaction in 7. The spin density distributions of 7 in both the high spin ground state and the broken symmetry state were obtained, and the spin coupling mechanism between Gd^3+ and Cr^3+ was discussed.  相似文献   

13.
采用NMR方法考察了室温和低温(-78~-60℃)下Pd2X2(dpm)2(X=NCO^-,CH3CO^-2,SCN^-和NO^-3,dpm=Ph2PCH2PPh2)与H2S在CD2Cl2或CDCl3中的反应。结果表明,在X=NCO^-和CH3CO^-2的情况下,H2S优先与这些Pd配合物的阴离子作用生成相应的共轭酸HX和Pd2(SH)2(dpm)2,后者在H2S存在下又进一步转化为Pd2(SH)  相似文献   

14.
Acylation reactions of 4,6-dimethoxyindoles with glyoxyloyl chlorides were achieved by the use of graphite powder in 1,2-dichloroethane at reflux. The products were monoketones as a result of decarbonylation, rather than the expected 1,2-diketones. Treatment of these monoketones with base led to their cyclisation and elimination of methanol to afford the novel dipyrrolo[2.3-a:1′,2′,3′-fg]acridin-12(1H)-ones.  相似文献   

15.
《Polyhedron》1999,18(5):729-733
Equimolar quantities of [Mo (CO) (η2-RC2R′)2Cp] [BF4] (R=R′=Me Ph R=Me R′=Ph) and L L′ or L″ {L L′ or L″= [WI2 (CO){PhP(CH2CH2PPh2)2-PP′} (η2-RC2R′)]} (L R=R′=Me L′ R=R′=Ph L″ R=Me R′=Ph) react in CH2Cl2 at room temperature to give the new bimetallic complexes[Mo (CO) (L L′ or L″–P) (η2-RC2R′)Cp] [BF4] (1–9) via displacement of the alkyne ligand on the molybdenum centre The complexes have been characterised by elemental analysis IR and 1 H NMR spectroscopy and in selected cases by 31 P NMR spectroscopy.  相似文献   

16.
《Chemical physics letters》2002,350(5-6):623-627
The ground states and binding energies of Eu3+–L (L=H2O,H2S,NH2CH3,S(CH3)2, imidazole) complexes has been determined using ab initio techniques. The binding is mostly electrostatic as expected. The empty f orbital is different for the S compounds, being a π-like orbital, while for the O and N containing ligands it is a σ-like orbital. However, the range in the binding energies for the different f holes is small.  相似文献   

17.
Abstract

Seven-coordinate complexes of molybdenum(II) and tungsten(II) have become increasingly important as homogeneous catalysts. For example, the complexes [MX2(CO)3L2] (M = Mo and W; X = Cl and Br; L = PPh3 and AsPh3) have been shown to be catalysts for the ring-opening polymerisation of norbornene.1 Although a wide variety of complexes of the type [MX2(CO)3L2] (M = Mo and W; X = Cl, Br and I; L = nitrogen, phosphorus, arsenic and antimony donor ligands)2 have been reported, until now no examples of the mixed complexes [MX2(CO)3(py)L] have been prepared. In this communication we wish to describe the synthesis of the new mixed pyridine/L compounds [MI2(CO)3(py)L] (M = Mo and W; L = PPh3, AsPh3 and SbPh3).  相似文献   

18.
19.
A new complex [Zn2(Ox)3]H2L · 4H2O (L = 2,2??-(1,4-butanediyl)-bis(1H-benzimidazole)) (I) has been hydrothermally synthesized and characterized by the elemental analysis, IR spectroscopy, and single crystal X-ray diffraction. It crystallizes in monoclinic space group P21/c with a = 10.108(2), b = 15.600(4), c = 9.768(2) ?, ?? = 105.289(3)·, V = 1485.7(6) ?3, Z = 4. Complex I is a 2D honeycomb-like polymer with pro-toned L and water molecules intercalating in the cavities. The luminescent spectra shows the emission peak of complex I is at 455 nm which is attributed to ligand-to-metal charge transfer.  相似文献   

20.
Systematic computational studies of stannylene derivatives SnX(2)/SnXY and XSnR/SnR(2)/RSnR' were carried out using density functional theory. The basis sets used for H, F, Cl, Br, C, Si, and Ge atoms are of double-ζ plus polarization quality with additional s- and p-type diffuse functions, denoted DZP++. For the iodine and tin atoms, the Stuttgart-Dresden basis sets, with relativistic small-core effective core potentials (ECP), are used. All geometries are fully optimized with three functionals (BHLYP, BLYP, and B3LYP). Harmonic vibrational wavenumber analyses are performed to evaluate zero-point energy corrections and to determine the nature of the stationary points located. Predicted are four types of neutral-anion separations, plus adiabatic ionization energies (E(IE)) and singlet-triplet energy gaps (ΔE(S-T)). The dependence of all three energetic properties upon choice of substituent is remarkably strong. The EA(ad(ZPVE)) values (eV) obtained with the B3LYP functional range from 0.70 eV [Sn(CH(3))(2)] to 2.36 eV [SnI(2)]. The computed E(IE) values lie between 7.33 eV [Sn(SnH(3))(2)] and 11.15 eV [SnF(2)], while the singlet-triplet splittings range from 0.60 eV [Sn(SnH(3))(2)] to 3.40 eV [SnF(2)]. The geometries and energetics compare satisfactorily with the few available experiments, while most of these species are investigated for the first time. Some unusual structures are encountered for the SnXI(+) (X = F, Cl, and Br) cations. The structural parameters and energetics are discussed and compared with the carbene, silylene, and germylene analogues.  相似文献   

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