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1.
Investigations on the Bismuth Rare‐Earth Oxyhalides Bi2REO4X (X = Cl, Br, I) Compounds of the composition of Bi2REO4X (RE = Y, La–Lu; X = Cl, Br, I) have been prepared by solid state reaction of stoichiometric mixtures of BiOX, Bi2O3, and RE2O3. They were characterized by X‐ray powder diffraction, IR spectroscopy, mass spectrometry and DTA/TG measurements as well. The crystal structure (tetragonal, P4/mmm, a ≈ 3.9 Å, c ≈ 9 Å) was determined by the Rietveld method. In the structure [M3O4]+ layers are interleaved by single halogen layers. Rare‐earth and bismuth atoms in Bi2REO4X are 8‐coordinated. The structure can be derived from the LiBi3O4Cl2 type structure. The enthalpies of formation are derived from heats of solution. The standard entropies were calculated from low‐temperature measurements of the specific heat capacities.  相似文献   

2.
Synthesis, Structure, and Properties of [nacnac]MX3 Compounds (M = Ge, Sn; X = Cl, Br, I) Reactions of [nacnac]Li [(2,6‐iPr2C6H3)NC(Me)C(H)C(Me)N(2,6‐iPr2C6H3)]Li ( 1 ) with SnX4 (X = Cl, Br, I) and GeCl4 in Et2O resulted in metallacyclic compounds with different structural moieties. In the [nacnac]SnX3 compounds (X = Cl 2 , Br 3 , I 4 ) the tin atom is five coordinated and part of a six‐membered ring. The Sn–N‐bond length of 3 is 2.163(4) Å and 2.176(5) Å of 4 . The five coordinated germanium of the [nacnac]GeCl3 compound 5 shows in addition to the three chlorine atoms further bonds to a carbon and to a nitrogen atom. In contrast to the known compounds with the [nacnac] ligand the afore mentioned reaction creates a carbon–metal‐bond (1.971(3) Å) forming a four‐membered ring. The Ge–N bond length (2.419(2) Å) indicates the formation of a weakly coordinating bond.  相似文献   

3.
Chemical reduction of B9X9 (X = Cl, Br, I) with gaseous HI proceeds stepwise to give the neutral paramagnetic clusters HB9X9 · , and the corresponding diamagnetic clusters H2B9X9. Together they comprise the first neutral derivatives in the series BnHn+1 and BnHn+2 with n = 9. The EPR spectra of the paramagnetic HB9X9 · (X = Cl, Br, I) in glassy frozen CH2Cl2 solutions showed increasing g anisotropy for the heavier halogen derivatives, illustrating significant halogen participation at the singly occupied MO due to the larger spin-orbit coupling contributions. Temperature dependent 1H NMR spectra of H2B9X9 (in CD3CN, X = Cl, Br) indicate the presence of H2B9X9, [HB9X9], and [CD3CNH]+ with H2B9X9 acting as a Brønsted acid. The corresponding 11B NMR spectra (in CD3CN) show the presence of the dianions [B9X9]2– as a result of the protonation of CD3CN. The 11B resonances of the species H2B9X9 and [HB9X9] are obscured by superimposition of the two resonance lines of the dianions [B9X9]2–. Temperature dependent 11B{1H} MAS-NMR spectra of H2B9Br9 show coalescence at 410 K and hence dynamic behaviour of the neutral B9-cluster in the solid. Cyclic voltammetry experiments of H2B9Br9 in CH3CN solvent) are compatible with the redox sequence [B9Br9]2––[B9Br9] · ––B9Br9. Quantum chemical calculations with the electron localization function (ELF) are described.  相似文献   

4.
Reaction of N-Trimethylmetal(IVb) Trialkylphosphine Imines with Hydrogen Halides Investigations of the reaction of N-trimethylmetal(IVb)-substituted phosphine imines with hydrogen have been carried out. With one mole of HX phosphonium halides of the general formula [R3P? NH? MMe3]X? (R = CH3, C2H5; M = Si, Ge, Sn; X = Cl, Br, J) are obtained. A second mole of HX causes M? N bond cleavage, yielding aminophosphonium halides, [R3P? NH2]X?.  相似文献   

5.
Geometry and thermodynamic characteristics of complexes X2MYH2 (M = Al, Ga, In; X = F, Cl, Br, I; Y = N, P, As) and their components were found by the B3LYP density functional method with the LANL2DZ(d,p) basic set. The nitrogen complexes X2MNH2 have a planar structure, whereas the phosphorus and arsenic complexes are pyramidal. Upon HX elimination, the dissociation energy of the M-Y bonds considerably increases (by 150-270 kJ mol- 1), which makes the dissociation of X2MYH2 into components thermodynamically unfeasible even at temperatures about 1000°C. A linear correlation between the dissociation enthalpies of M-Y bonds in the X3MYH3 and X2MYH2 complexes was found for each central atom M, which makes it possible to estimate the dissociation enthalpies of coordination-unsaturated compounds of the Group IIIa elements from the dissociation enthalpies of their coordination-saturated analogs. The enthalpies of dimerization of X2MYH2 fall in the range from 40 (Y = P, As) to 260 kJ mol- 1 (Y = N), which makes the process X3MNH3 = [X2MNH2]2 + HX with the retention of the metal-nitrogen bond more favorable than the dissociation of the initial complex into the components. Thus, dimers [X2MNH2]2 can be intermediates in chemical deposition of nitrides from the gas phase of donor-acceptor complexes.  相似文献   

6.
Low-Temperature Synthesis of Oxyhalides, YOX (X = Cl, Br, I), as the Source of Impurity in the Preparation of Trihalides, YX3, via the Ammonium Halide Route. Analogy of YOCl and YSCl Ammonium halides, NH4X (X = Cl, Br, I), react with Y2O3 and Y2S3, respectively, at temperatures as low as 230=C (X = Cl), 280=C (Br), and 360=C (I) (molar ratio 12:1) to yield (NH4)3YX6, NH3, and H2O (H2S). The choice of smaller ratios than 12:1 (for example 2:1) results in the formation of oxyhalides, YOX, via the reaction of (NH4)3YX6 with surplus Y2O3. This reaction is therefore the actual source of impurity of rare-earth trihalides in their preparation via the ammonium halide routes.  相似文献   

7.
Hydrolysis and Halide Exchange of Pentahalogenomonocarbonyl Osmates(III) The aquo complexes [OsX4(CO)(H2O)]?, [OsX3(CO)(H2O)] and [OsX2(CO)(H2O)3]+, X ? Cl, Br, I, produced by the stepwise hydrolysis of [OsX5(CO)]2?, are isolated as pure solutions by ionophoresis and characterized by their absorption spectra. Due to stability of the monaquo complexes and the different trans-effect of the halides it is possible to prepare the mixed complexes [OsX4–nYn(CO)(H2O)]?, X ≠ Y = Cl, Br, I, n = 1–3, and for n = 2 the pure stereoisomers are formed. A systematic shift is found in charge-transfer bands to the shorter wavelengths when the halides are replaced by H2O, I by Br or Cl and Br by Cl.  相似文献   

8.
Preparation and Characterization of [Pt(mal)2]2? and trans-[Pt(mal)2X2]2? (X = Cl, Br, I, SCN) By twofold treatment of K2[PtCl4] with potassium hydrogen malonate in a queous solution the yellow K2[Pt(mal)2] · H2O is obtained. After extraction with tetrabutylammonium ions into dichloromethane by oxidative addition at ?90°C the PtIV complexes [Pt(mal)2X2]2?, X = Cl, Br, I, SCN, are formed. The SCN ligands are coordinated to Pt via S. The IR and Raman spectra are discussed and assigned.  相似文献   

9.
A theoretical analysis has been made of differences in relaxation energies for photoionization from the core levels of the series X2, HX for X = F, Cl, Br. It is demonstrated that whilst the charge in relaxation energies is largest for F2 with respect to HF, the contribution to the shifts in core levels is relatively larger for the series X2 and HX for X = Cl, Br. It is further shown that shifts in binding and relaxation energies show very little dependence on the core levels studied.  相似文献   

10.
Organometallic Compounds of Copper. XVIII. On the Reaction of the Alkyne Copper(I) Complexes [CuX(S‐Alkyne)] (X = Cl, Br, I; S‐Alkyne = 3,3,6,6‐Tetramethyl‐1‐thiacyclohept‐4‐yne) with the Phosphanes PMe3 and Ph2PCH2CH2PPh2 (dppe) The alkyne copper(I) halide complexes [CuX(S‐Alkyne)]n ( 2 ) ( 2 a : X = Cl, 2 b : X = Br, 2 c : X = I; S‐Alkyne = 3,3,6,6‐tetramethyl‐1‐thiacyclohept‐4‐yne; n = 2, ∞) add the phosphanes PMe3 and Ph2PCH2CH2PPh2 (dppe) to form the mono‐ and dinuclear copper compounds [(S‐Alkyne)CuX(PMe3)] ( 6 ) ( 6 a : X = Cl, 6 b : X = Br) and [(S‐Alkyne)CuX(μ‐dppe)CuX(S‐Alkyne)] ( 7 a : X = Cl, 7 b : X = Br, 7 c : X = I), respectively. By‐product in the reaction of 2 a with dppe is the tetranuclear complex [(S‐Alkyne)Cu(μ‐X)2Cu(μ‐dppe)2Cu(μ‐X)2Cu(S‐Alkyne)] ( 8 ). In case of the compounds 7 prolonged reaction times yield the alkyne‐free dinuclear copper complexes [Cu2X2(dppe)3] ( 9 ) ( 9 a : X = Cl, 9 b : X = Br, 9 c : X = I)). X‐ray diffraction studies were carried out with the new compounds 6 a , 6 b , 7 b , 8 , and 9 c .  相似文献   

11.
The following zinc(II), cadmium(II) and mercury(II) complexes of 2-methyl-benzoselenazole (L) have been prepared and studied by conductometric and i.r. methods: MLX2 (M ? Cd, Hg, X ? Cl, Br, I), ML1.5X2 (M ? Zn, X ? ClO4(4 H2O); M ? Hg, X ? NO3, ClO4), ML2X2 (M ? Zn, X ? Cl, Br, I, NO3; M ? Cd, X ? NO3, ClO4). The ligand is N-bonded. All the anions are coordinated.  相似文献   

12.
The 13C NMR spectra of a number of iridium complexes and of their adducts with H2, HX, and Cl2 (X = Cl, Br, I) are used to estimate the redox character of these additions. Rather than having the oxidative character expected, H2 addition seems to be reductive. HX and Cl2 additions are oxidative. Some of these complexes appear to have Lewis acid, rather than the expected Lewis base character.  相似文献   

13.
Summary Complexes of manganese(II) with the tridentate oxime ligand 2,6-diacetylpyridine dioxime (H2dapd) have been synthesized and characterized. The complexes [Mn(H2dapd)X2] are pentacoordinate for X = Cl, Br or I but apparently octahedralvia bridging anions for X = NCS or NCSe. The complex [Mn(H2dapd)(NO3)2] adopts an octahedral structure involving monodentate and bidentate coordination of nitro groups. The complexes [Mn(H2dapd)2]X2 (X = Cl, Br, I, NO3, NCS or NCSe) involve an octahedral cation.  相似文献   

14.
Single-Crystal X-Ray Analysis of Compounds with a Covalent Metal-Metal Bond. VII. Crystal and Molecular Structure of the Halogeno-Bridged Dimers of Halogenobis(pentacarbonylrhenium)indium(III), [(Re(CO)5)2In(μ-X)]2 (X = Cl, Br, I) [(Re(CO)5)2In(μ-X)]2 crystallizes if X = Cl and X = Br in the monoclinic system, space group P21/c (No. 14), with the lattice constants X = Cl: a = 10.540(6), b = 12.961(7), c = 26.071(12) Å, β = 106.3(1) Å, Z = 4, X = Br: a = 10.548(9), b = 13.108(7), c = 26.192(15) Å, β = 106.0(2)°, Z = 4 and if X = I in the triclinic system, space group P1 (No. 2), with the lattice constants a = 10.739(2), b = 7.160(1), c = 13.647(1) Å, α = 68.65(9), β = 71.89(9), γ = 65.52(9)°, Z = 1. The central molecular fragment consists of a plane In2X2 ring with the mean In—X distances: X = Cl: 2.624(6) Å, X = Br: 2.764(3) Å and X = I: 2.986(2) Å and the angles In—X—In/X—In—X, X = Cl: 97.2(2)°/ 82.8(2)°, X = Br: 94.8(1)°/85.2(1)° and X = I: 96.47(5)°/83.53(5)°. Two Re(CO)5 groups are bonded to each of these In atoms to form a distorted tetrahedral coordination. The mean In—Re bond-distances are: X = Cl: 2.797(2), X = Br: 2.796(2) and X = I:2.811 (2) Å. There is a octahedral coordination around the Re atoms.  相似文献   

15.
Emission resulting, from collisions of 5–200 eV electrons with gaseous HgX2, and CH3HgX (X = Cl, Br. I) was characterized in the 3800–5600 A region. HgX BX emission dominates and absolute cross section as a function of electron energy were determined. The formation of electronically excited Hg atoms, and the trend of the cross sections with the nature of the halogen atom are discussed in terms of a simple charge transfer model.  相似文献   

16.
Synthesis and Structure of two Mixed Substituted Dialanes Al2X2{Si(SiMe3)3}2 · 2 THF (X = Cl, Br) The syntheses of tris(trimethylsilyl)silyl (hypersilyl) and halide substituted dialanes Al2X2{Si(SiMe3)3}2 · 2 THF (X = Cl, Br) are presented. The results of the X‐ray diffraction experiments are presented and discussed in comparison to the AlIII compounds AlBr2Si(SiMe3)3 · THF and AlBr3 · OPh2.  相似文献   

17.
The complexes Zn(DMBCTA)X2 (X = Cl, Br or I), Cd7(DMBCTA)4Cl14, Cd(DMBCTA)X2 (X = Br or I) and Hg(DMBCTA)X2 (X = Cl, Br or I; DMBCTA = N,N-Dimethylbenzenocarbothioamide) were isolated and characterized by elemental analysis, conductance and molecular weight measurements, and IR, Raman, and 1H NMR spectroscopy.  相似文献   

18.
Bis(disulfide)bridged Nb(+4) cluster halide complexes [Nb2S4X8]4– (X = Cl, Br) were prepared by acid hydrolysis of [Nb2S4(NCS)8]4– in concentrated aqueous HCl or HBr, solution from which they can be isolated as double salts Cs5[Nb2S4X8]X (X = Cl, 1 ; X = Br, 2 ). The crystal structures of 1 and 2 were determined. The isolation and X-ray structure of oxonium salt (H3O)5 [Nb2S4Cl8]Cl ( 3 ) is also reported. 1 – 3 contain new [Nb2S4X8]4– anions which can also be viewed as excised building blocks of polymeric solids NbS2X2. The extra halogen resides in the center of octahedron formed by six Cs+ or H3O+ ions. All the three salts are isostructural and crystallize in tetragonal space group Immm with the following parameters: a = 10.269(2), b = 16.343(2), c = 7.220(1) Å for 1 , a = 10.934(1), b = 16.613(2), c = 7.470(1) Å for 2 , a = 9.639(1), b = 16.031(1), c = 7.071(1) Å for 3 . The parameters of the Nb2S4 core are only slightly affected by the change from Cl to Br.  相似文献   

19.
Contributions to the Chemistry of Niobium and Tantalum. 88. Cluster Hydroxides [M6X12](OH)2 · 8 H2O with M = Nb, Ta; X = Cl, Br The cluster hydroxides [M6X12](OH)2 · 8 H2O with M = Nb, Ta; X = Cl, Br, have been prepared. The poor crystalline compounds could not be classified in any of the four general structure patterns of the niobium and tantalum halide compounds. Infrared spectra, magnetic and thermal behaviours of the compounds have been measured and discussed.  相似文献   

20.
Kinetic and Equilibrium Studies on Aquation and Halide-Anation of Osmium(IV)- Halogeno-Aquo Complexes Complexes of type [OsI5X]2? (X = Cl, Br, I) undergo hydrolysis in acidic, aqueous solutions already at room temperature according to [OsI5X]2? + H2O ? [OsI5(H2O)]? + X?. Rate constants of aquation and anation reactions as well as equilibrium constants are determined by spectrophotometrical measurements. The kinetic and equilibrium experimental results are giving similar thermodynamic data. Kinetic stability increases from I over Br to Cl whereas the thermodynamic stability decreases in the same order. The monoaquo complex is less stable than the hexahalo complexes by 2 kcal/mol, and is present as an intermediate product in the halogen exchange reactions carried out in dilute solutions.  相似文献   

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