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1.
The complexes [Zn(en)3]X2·n H2O, where en = ethylenediamine, X = Cl?, Br? or 12SO2?4, n = 1 or 0.5, and [Zn(tn)2]X2·n H2O, where tn=1,3-diaminopropane, X=Cl?, Br? or 12SO2?4, n = 0 or 0.25, have been synthesized and their thermal investigations carried out. The complexes were characterized by elemental analysis and IR spectral data. These complexes have been observed to decompose through several isolable as well as non-isolable complex species as intermediates during heating. [Zn(tn)2]SO4 undergoes solid-state phase transition in the temperature range 126–145°C. ZnenSO4 and ZntnX2 (X = Cl?, Br? or 12SO2?4) have been synthesized pyrolytically in the solid state from their corresponding mother diamine complexes. ZnenSO4 and ZntnX2 (X = Cl?, Br? or 12SO2?4) complexes decompose through non-isolable hemidiamine species. ZnX2 (X = Cl? or Br?) complexes of tn undergo melting after formation of the monodiamine species. In contrast, the corresponding en complexes undergo melting at non-stoichiometric composition. Diamine (en or tn) is found to be bridging in all monodiamine (en or tn) complexes; whilst their mother complexes possess chelated en or tn. The thermal stability sequence of en and tn complexes of Zn(II) is ZnCl2 < ZnBr2 < ZnSO4. ΔH values are reported for some steps of decomposition. Possible mechanistic paths have been reported for each step of decomposition.  相似文献   

2.
The extraction of In(III) from 1M (Na,H)(Cl,ClO4) media with 4-acylpyrazol-5-ones (HL) in toluene at 25°C is described by equilibria In 3+ + 3 HL ? InL3 + 3 H+ (log K = 1.48, 1.03, 0.87 with acyl = benzoyl, lauroyl, 2-thenoyl), InCl 2+ + 2 HL ? InClL2 + 2 H+ (log K = 0.26, ?0.45, ?0.35 respectively) and In3+ + m Cl? ? InClm(3-m)+ (log βm available from literature). The extraction from 1M (Na,H)(Cl,NO3) medium is enhanced by addition of aliquat (TOMA+,Cl?) and the following synergic equilibrium takes place : InCl2 + (TOMA+,Cl?) ? (TOMA+, InCl2L2? (log K = 5.49, 5.25, 5.21 respectively). Cl? of (TOMA+,Cl?) is exchanged by NO3? with the equilibrium constant log K = 1.50. If (TOMA+,Cl?) is replaced by tri-n-octylammonium chloride, the synergic effect is largely reduced (log K = 4.17 with acyl = benzoyl). The extraction from chloride solutions containing ClO4? remains unchanged by addition of ammonium salts.  相似文献   

3.
We have measured the ionic conductivities of pressed pellets of the layered compounds MUO2PO4 · nH2O, and correlated the results with TGA data. The conductivities (in ohm?1 m?1), at temperatures increasing with decreasing water content over the range 20 to 200°C, were approximately as follows: Li+4H2O, 10?4; Li+, Na+, K+, and NH4+3H2O, 10?4, 10?2, 10?4, and 10?4; H+, Li+, and Na+1.5H2O, 10?2, 10?4, and 10?4; Na+1H2O, 10?5; H+, K+, and NH4+0.5H2O, all 10?5; and H+, Li+, Na+, K+, NH+4, and 12Ca2+OH2O, 10?5, 10?5, 10?4, 10?5, 10?5, and 10?6. A ring mechanism is proposed to account for the high conductivity found in NaUO2PO4 · 3.1H2O. The accurate TGA data showed that most of the hydrates had water vacancies of the Schottky type, and should be represented as MUO2PO4(A ? x)H2O, where x can be between 0 and 0.3.  相似文献   

4.
The solid-state kinetics for the olation reactions of [Co(NH34(OH)(H2O)]X2 (where X  Cl?, Br?, or 12SO2?4 were determined by several different methods using dynamic and isothermal thermogravimetric data. For the reduced-time plot method, E values were 20, 43, and 25 kcal mol?1 for the chloride-bromide, and sulfate complexes, respectively. For the Jacobs and Kureishy method, E values of 21, 37, and 17 kcal mol?1, were obtained for the above three complexes, respectively. A possible reaction pathway is suggested for the olation reaction.  相似文献   

5.
The thermal dissociation of the [Co(NH3)6]X3 (X = Cl?, Br?, I?, and NO?3), [Co(en)3]X3 (X = Cl?, Br?, I?, NO?3, HSO?4 and 12 C2O2?4), cis- [Co(en)2Cl2]Cl, and trans-[Co(en)2ClBr]NO3 complexes was investigated by an electrical conductivity (EC) technique. During the thermal dissociation reactions, liquid or semi-liquid phases are formed which cause large increases in the EC of the compound. The effect of concentration of the complex in a matrix medium as well as the composition of the matrix material on the EC curves were also determined.  相似文献   

6.
Translational diffusion, velocity sedimentation and viscometry of polyamidobenzimidazole (PABI) solutions in the range of M = (1–61) · 103 have been investigated in N,N-dimethylacetamide (DMA) and 98% H2SO4. The dependences of D0, S0 and [η] on M were obtained. Tsvetkov-Klenin's hydrodynamic invariant was found to be A0 = 3.55 · 10?10erg deg?1mol?13. The equilibrium rigidity of PABI molecules was characterized by the length of the Kuhn segment A = 250 ± 100 A?. The chain diameter was 7 ± 4 A?. The values of A in 98% H2SO4 and in an aprotic solvent, DMA, were virtually identical, implying that the rigid-chain conformation of PABI molecules in 98% H2SO4 is due to their geometrical structure rather than to the protonization of amide bonds. The significance of the latter evidently increases in PABI solutions in 100% H2SO4 in which A is 1.5 times as high. The decrease in rigidity of PABI as compared to that of poly-p-phenylene terephthalamide (A = 400 ± 100 A?) is in reasonable agreement with the presence of imidazole rings in PABI molecules. The presence of these rings results in kinks in the PABI chain with angles of about 30° and hence, in the depature from parallelism of rotating bonds.  相似文献   

7.
The metal chelates of 1-acetylpyridinium chloride-4-phenyl-3-thiosemicarbazide [(APTS)]+Cl? of the type [M(APTS)X2]+ Cl? (M = Co(II), Ni(II), Cu(II), Zn(II) or Cd(II); X = Cl, Br or 12SO4) have been prepared and characterized on the basis of elemental analysis, molar conductance, IR, electronic spectra and magnetic studies. IR spectral studies showed that the ligand coordinates via thioketo and NLH groups. Magnetic and spectral studies suggest a tetrahedral structure for Ni(II), pseudo-tetrahedral for Co(II) and square planar and/or distorted tetrahedral for Cu(II) chelates.  相似文献   

8.
The colourless, six- and seven-membered manganacycloalkanes (OC)4MnPR2OCH2XCH2 are obtained by reaction of Na2[(OC)4MnPR2O] with the bis(triflate)alkanes (YCH2)2X (R = C6H5; X = CH2, C(CH3)2, CH2CH2; Y = CF3SO3). CO or SO2 can be inserted into the reactive MnC-σ bonds under ring expansion. Some characteristic IR and 1H NMR data are discussed. (OC)4MnPR2OCH2CH2CH2 crystallizes monoclinic in the space group P21/c with Z = 4.  相似文献   

9.
The extraction of Co(II) with mixtures of 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-one ((H)PMBP) and tri-n-octylamine (TOA) is investigated in order to explore the influence of diluents and inorganic anions with synergistic acidic extractant + liquid anion exchanger systems. Although it is proved that the same species [HTOA]+ [Co(PMBP)3]? is extracted from various inorganic media, with toluene as the diluent, the presence of ClO4? SO42? or Cl? anion modifies the distribution of the anions which are associated to (HTOA)+ in the organic phase, leading to different synergistic equilibria; with Cl? or SO42?: CO(PMBP)2 + (HTOA+,PMBP?) ?(HTOA+,Co(PMBP)3? (log K = 6.10) and with ClO4? : Co(PMBP)2 + HPMBP + (HTOA+,ClO4? ? (HTOA+,Co(PMBP)3? + H+ + ClO4? (log K = 2.34) The same synergistic equilibrium is observed for the extraction of Ni(II) from ClO4? medium, with a comparable value of the constant (log K = 2.45). The synergistic effect is cancelled in n-octanol.  相似文献   

10.
New copper (II) complexes of Schiff bases with 1,2-di(imino-2-aminomethylpyridil)ethane with the general composition CuLX m (H2O) x , [L = Schiff base, X = Cl?, Br?, NO3 ?, ClO4 ?, CH3COO?, m = 2; X = SO4 2?, m = 1] were prepared by template synthesis. The complexes were characterized by elemental analysis, conductivity measurements, magnetic moments, IR, UV–VIS and EPR spectra. The thermal behavior of complexes was studied using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Infrared spectra of all complexes are in good agreement with the coordination of a neutral tetradentate N4 ligand to the cooper (II) through azomethinic and pyridinic nitrogen. Magnetic, EPR and electronic spectral studies show a monomeric distorted octahedral geometry for all Cu(II) complexes. Conductance measurements suggest the non-electrolytic nature of the compounds, except for copper (II) nitrate and perchlorate complexes which are 1:2 electrolytes. Heats of decomposition, ΔH, associated with the exothermal effects were also determined.  相似文献   

11.
The syntheses of two new monothiocarbamate ligands and selected transition element complexes of each are reported. The complexes of indoline-N-carbothioate (intc) prepared are: NiL2·1.5H2O, ZnL2, NiL2·2py, ZnL2·2py. The complexes of indole N-carbothioate (iltc) are: NiL′2, ZnL′2, Cul′. IR spectral results support a bidentate ligand behavior for both new monothiocarbamates except in ZnL2·2py. Comparison of the IR spectral features of bis(indolylcarbamoyl)-disulfide with that of coordinated indole-N-carbothioate allowed an assignment of the C-S and C-O vibrational frequencies. Evidence for differences in major resonance contributions to the electronic structures of each new ligand are presented. The crystal structure of the bis(indolylcarbamoyl)disulphide is also presented and a comparison is made to pyrrole-N-carbothioate, another aromatic amine monothiocarbamate. The disulphide crystallizes in the centrosymmetric monoclinic space group P21/c with a = 15.64(4)Å, b = 5.228(1)Å, c = 19.271(7)Å, β = 97.20(2)°, V = 1564(1)Å3, d(obsd)(calcd) = (1.50)(1.52) for a molecular weight = 356.1 and Z = 4. Diffraction data were collected with a Syntex P1- diffractiometer with CuKα radiation. Least squares refinement resulted in Rf = 7.0% for all 1213 non zero reflections have (I)> 3σ(I).  相似文献   

12.
The structure of NiI2, 6 H2O has been determined by X-ray diffraction techniques. The dimensions of the hexagonal unit cell are: a = 7.638 ± 0.005 Å and c = 4.876 ± 0.005 Å, with Z = 1. The space group is P3m1. The structure was deduced from Patterson and Fourier syntheses and refined by least-squares method to a final R value of 0.09. It is almost a layer structure, each layer is composed by n complex ions [Ni(H2O)6]2+ surrounded by 2 n ions I?; this is in agreement with the good cleavage of crystals and with the marked anisotropy in the thermal expansion. But the structure may also be regarded as a derivation of NiAs structure, with only 18 of octahedral holes occupied. A structural classification of compounds MX2, 6 H2O is proposed.  相似文献   

13.
Infrared spectra of new iron(III) complexes with urea derivatives: [Fe (CH3HNCONH2)6]X3; [Fe(C2H5HNCONH2)6]X3 and [Fe(CH3-HNCONHCH3)6]X3 (where X = Cl?, NO?3 or 12SO2?4) have been recorded and their interpretation given. The analysis of the infrared spectra was based on a comparison of the positions of bands corresponding to the vibrations of characteristic groups appearing in the complexes and the free ligands. Comparison and analysis of the data show that the urea derivatives coordinate with mono- and disubstituted iron(III) through the oxygen atom of the carbonyl group.  相似文献   

14.
Nickel-ammonium tetrametaphosphate, Ni(NH4)2P4O12 · 7H2O is triclinic with a = 13.841(3); b = 9.621(5); c = 7.482(2)Å; α = 98.05(4); β = 97.25(4); γ = 103.01(4)°; M = 536.59; V = 947.9Å3; Z = 2; Dx = 1.879 g cm?3; μ = 14.524 cm?1, and space group P1. The crystal structure was solved using 1661 independent reflections measured on a single-crystal diffractometer (Mo). The final R value is 0.056. The two crystallographic independent nickel atoms Ni(1) and Ni(2) are octahedrally coordinated: Ni(1) by four oxygen atoms and two water molecules, Ni(2) by six water molecules. Ni(1), closely connected to two P4O12 rings, forms a complex anion [Ni(P4O12)2(H2O)2]6? which is associated to ammonium polyhedra and [Ni(H2O)6]2+ octahedra. Another interesting feature of this atomic arrangement is the presence of a large channel (10 × 4) Å2 parallel to the c axis. The internal surface of this channel is covered by six zeolitic water molecules.  相似文献   

15.
The new compound Nb3Se5Cl7 was prepared by heating 2NbSe2Cl2 + 1NbCl4 at 530°C for 2–3 weeks. The compound is monoclinic with a = 7.599, b = 12.675, c = 8.051Å; β = 106.27°; space group P21m. The corresponding bromide, Nb3Se5Br7 (obtained by decomposition of NbSe2Br2 under NbSeBr3), is isotypic with a = 7.621, b = 12.833, c = 8.069Å; β = 106.21°. from the crystal structure and XPS spectra it follows that Nb3Se5Cl7 can be formulated as: [Nb4+2Nb5+1(Se2)2?2Se2?1Cl?7]. The structure consists of chains of composition [Nb4+2(Se2)2?2Cl?5], to which side chains [Nb5+Se2?Cl?2] are attached. The Nb4+ atoms form pairs (NbNb = 2.94 Å) which explains that Nb3Se5Cl7 is a diamagnetic semiconductor with a band gap (1.59 eV at 5°K, 1.49 eV at 300°K) very similar to that of NbSe2Cl2.  相似文献   

16.
Two new potentially octadentate N2O6 Schiff-base ligands 2-((E)-(2-(2-(2-((E)-2-hydroxy-3-methoxybenzylideneamino)phenoxy)phenoxy)phenylimino)methyl)-6-methoxyphenol H2L1 and 2-((E)-(2-(2-(2-((E)-2-hydroxy-3-methoxybenzylideneamino)phenoxy)-4-tert-butylphenoxy)phenylimino)methyl)-6-methoxyphenol H2L2 were prepared from the reaction of O-Vaniline with 1,2-bis(2′-aminophenoxy)benzene or 1,2-bis(2′-aminophenoxy)-4-t-butylbenzene, respectively. Reactions of H2L1 and H2L2 with copper(II) and zinc(II) salts in methanol in the presence of N(Et)3 gave neutral [CuL1]?·?0.5CH2Cl2, [CuL2], [ZnL1]?·?0.5CH2Cl2, and [ZnL2] complexes. The complexes were characterized by IR spectra, elemental analysis, magnetic susceptibility, ESI–MS spectra, molar conductance (Λm), UV-Vis spectra and, in the case of [ZnL1]?·?0.5CH2Cl2 and [ZnL2], with 1H- and 13C-NMR. The crystal structure of [ZnL1]?·?0.5CH2Cl2 has also been determined showing the metal ion in a highly distorted trigonal bipyramidal geometry. The electrochemical behavior of H2L2 and its Cu(II) complex, [CuL2], was studied and the formation constant of [CuL2] was evaluated using cyclic voltammetry. The logarithm value of formation constant of [CuL2] is 21.9.  相似文献   

17.
(C5H5)2NbBH4 reacts with C5H5M(CO)3Me in toluene solution in the presence of Et3N to give binuclear complexes (C5H5)2NbM(CO)3C5H5 where M is Mo or W (IV and V, respectively). The structure of IV has been studied by X-ray diffraction (the crystals are orthorhombic, a 12.748(5), b 16.745(6), c 14.314 A/ac>?;; Z = 8, space group of Pbca, automatic difractometer Syntex P2I, λ(Mo-Kα, 1382 reflections, R = 0.056, Rw = 0.058). Molecule IV contains a wedge-like sandwich (π-C5H5)2Nb (NbC 2.37–2.48, CC (av) 1.42 A/ac>?;, angle between ring planes 49°) linked with the (π-C5H5)Mo(CO) fragment by a direct NbMo bond (3.073 A/ac>?;) and two bridging CO groups, one nonsymmetrically bonded through the carbon atom only (CO 1.17, NbC 2.53, MoC 2.02 A/ac>?;) and the other σ-bonded to Mo (MoC 1.944 A/ac>?;) and π-bonded to Nb (CO 1.22, NbC 2.22, NbO 2.26 A/ac>?;). Three types of carbonyl groups present in IV give rise to strong IR bands at 1870, 1700 and 1560 cm?1 assigned to the terminal, μ-bridging and σ, π-bridging CO groups respectively. Complex IV has a similar structure. The electronic structure of IV and its dissociation across the NbMo bond are discussed.  相似文献   

18.
For a number of fractions and unfractionated samples of polylaurolactam, molecular weights (Mw = 1 × 104?12·5 × 104) were measured by the light-scattering method in a mixed solvent of m-cresol with 60 vol. % 2,2,3,3-tetrafluoropropanol; intrinsic viscosities were determined in m-cresol and 96% H2SO4, and the constants of the Mark-Houwink equation were calculated. The calculated values of the characteristic ratio of unperturbed dimensions (virtually identical for m-cresol and 96% H2SO4) were compared with the respective values for polypyrrolidone and polycaprolactam. It was found that the higher frequency of the CONH-groups reduces the rigidity of the polyamide chain.  相似文献   

19.
Isothermal cells of nickel with diamon windows were used to study various melts and vapours by infrared emission, transmission and reflectance techniques in the 860 to 300 K range with an evacuable Fourier transform spectrometer.IR vapour spectra of AlX3 (X = Cl, Br, I) and GaCl3 in transmission and emission were measured between 700 and 50 cm?1. A comparable signal/noise ratio between the transmission and emission spectra was obtained above 200 cm?1, below 200 cm?1 the transmission spectra had better quality. The dimer and monemer spectra were assigned in terms of D2h and D3h symmetry, respectively, and compared with earlier Raman and IR matrix isolation data.Emission spectra of chloroaluminates AlkAlCl4 (Alk = Li, Na, K, Rb, Cs) were recorded as melts between 1500 and 50 cm?1. Increasing distortion of the tetrahedral AlCl?4 ion in the series Cs<Rb<K<Na<Li was observed. Emission spectra of AlkAl2Cl7 (Alk = Li, Na, K, Cs) indicate D3d symmetry for Al2Cl?7 with a linear Al-Cl-Al bridge as proposed from earlier Raman data. As a demonstration of reflectance technique an IR spectrum of ZnAl2Cl8 at ambient temperature is presented.  相似文献   

20.
Ionic trifluoromethanesulphonates (triflates) are strongly solvated with their conjugate acid in dichloromethane (Ph3C+, n-Bu4N+, Ag+) and acetonitrile (Na+, Ag+). A 1H and 19F NMR study of the chemical shifts of various acid-salt mixtures show that in CH2Cl2 three homoconjugates A? · HA, A?. (HA)2 and A?(HA)3 were formed with large formation constants whereas in acctonitrile only the 1:1 homoconjugate was formed with an equilibrium constant K1 ~ 4 1 · M?1. This result explains why the protonation by CF3SO3H of non-polymerizable olefins such as 1,1-diphenylethylene and 3-phenylindene is always incomplete (13 and 12 respectively) in CH2Cl2. Conditions in which covalent triflates could be obtained have been investigated. As a consequence of homoconjugation, reaction of Ph3COH with triflic anhydride led to Ph3C+ CF3SO?3 HOSO2CF3. Other tertiary alcohols were dehydrated by triflic anhydride and led to ethylenic compounds (1,1-diphenylethanol) or ethers (2-phenyl 2-propanol). Esters were only observed in the case of benzyltriflate (at ?20°) and in the case of 1-phenylethyltriflate which is a model of polystyryltriflate (stable at room temperature).  相似文献   

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