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1.
 The optical absorption, photoluminescence, and photoconductivity spectra of some compounds of the formulas [R(CH2) n NH3] x M y X z , [R(CH2) n NH(CH3)2] x M y X z , [R(CH2) n S(CH3)2] x M y X z , [R(CH2) n SC(NH2)2] x M y X z , and [R(CH2) n SeC(NH2)2] x M y X z (R = organic residue; M = Bi(III), Pb(II), Sn(II), Cu(I), Ag(I) etc; X = I, Br, Cl; n, x, y, z = 0, 1, 2, 3, …) are briefly reviewed, and some new results are reported. The position, intensity, and shape of the excitonic bands depend on the dimensionality and size of the inorganic network as well as on the nature of the M, X, R, and onium moieties.  相似文献   

2.
A series of the mixed transition metal compounds, Li[(Ni1/3Co1/3Mn1/3)1–x-y Al x B y ]O2-z F z (x = 0, 0.02, y = 0, 0.02, z = 0, 0.02), were synthesized via coprecipitation followed by a high-temperature heat-treatment. XRD patterns revealed that this material has a typical α-NaFeO2 type layered structure with R3- m space group. Rietveld refinement explained that cation mixing within the Li(Ni1/3Co1/3Mn1/3)O2 could be absolutely diminished by Al-doping. Al, B and F doped compounds showed both improved physical and electrochemical properties, high tap-density, and delivered a reversible capacity of 190 mAh/g with excellent capacity retention even when the electrodes were cycled between 3.0 and 4.7 V.  相似文献   

3.
Organosilicon gels [Co(NH2R2)2Cl2] and [Cr(NH2R2)3Cl3], containing a diaminodichloride complex of cobalt(II) and triaminotrichloride complex of chromium(III) (R2 = CH2CH2CH2SiO(OEt)), were synthesized by the hydrolysis of complexes [Co(NH2R1)2Cl2] (I) and [Cr(NH2R1)3Cl3] (II) incorporating peripheral triethoxysilyl groups (R1 = CH2CH2CH2Si(OEt)3). The coprecipitated [Co(NH2R2)2Cl2] · 4NH2R3, [Cr(NH2R2)3Cl3] · 6NH2R3, [Co(NH2R2)2Cl2] · 2SiO2, and [Cr(NH2R2)3Cl3] ·xSiO2 · (3 – x)SiHO1.5 (R3 = CH2CH2CH2SiO1.5) gels were obtained by cohydrolysis of complexes I and II with 3-aminopropyltriethoxysilane or triethoxysilane. Interaction with SiH(OEt)3 is accompanied by the decomposition of silicon hydride groups and the formation of tetraethoxysilane derivatives. The heating of dry gels in a flow of argon or oxygen to 600° results in the formation of amorphous silica having a specific surface area 2–467 m2/g and containing crystalline metals, their chlorides, oxides, silicates, or carbides.  相似文献   

4.
Routes for synthesizing intercalation compounds of aluminum hydroxide [MxAly(OH)z]n X · pH2O (M=Li, Mg, Ni, Co, …) are suggested, and application of these schemes to syntheses of nanoscale systems is examined. It is shown that nanoscale systems varying in composition, structure, and morphology may be obtained according to the nature of anion X and reaction conditions. Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch, Russian Academy of Sciences (Novosibirsk). Translated fromZhurnal Strukturnoi Khimii, Vol. 39, No. 3, pp. 453–459, May–June, 1998.  相似文献   

5.
Summary.  The structure of the dehydrogenation product 1′,3a′-dihydro-3′-((1,3-dioxoindan-2-ylidene)-phenyl-methyl)-5′-phenyl-spiro-(indan-2,1′-pyrrolo[3,4-c]pyrrole)-1,3,4′,6′-(5′H, 6a′H)-tetrone derived from the cycloadducts (±)-(3a′S,6a′R)-1′,3a′-dihydro-3′-((R)-α-(1,3-dioxoindanyl)-benzyl)-5′-phenyl-spiro-(indan-2,1′-pyrrolo[3,4-c]pyrrole)-1,3,4′,6′(5H,6a′H)-tetrone and/or (±)-(3a′S,6a′R)-1′,3a′-dihydro-3′-((S)-α-(1,3-dioxoindanyl)-benzyl)-5′-phenyl-spiro-(indan-2,1′-pyrrolo[3,4-c]pyrrole)-1,3,4′,6′(5H,6a′H)-tetrone, which were synthesized by 1,3-dipolar cycloaddition of N-phenylmaleimide to 2-((2-(1,3-dioxoindan-2-yl)-2-phenyl-ethenyl)-imino)-indan-1,3-dione, was determined by X-ray analysis. Crystal data (CCD, 180 K): rhombohedral, R&3macr;;, a = 34.0871(7), c = 13.9358(5) ?, Z = 18; the structure was solved by direct methods and refined by full-matrix least-squares procedures to R(F, I ≥ 3σ(I)) = 0.053. The molecule contains a central folded ring system of two cis-fused 5-membered heterocyclic rings; each ring is nearly planar, and the angle between the rings amounts to 59.0°. Dynamic 1H NMR spectroscopy of the product revealed an exchange process caused by restricted rotation of the double bonded 1,3-indandione moiety and the phenyl group about the Csp2-Csp2 single-bonds. Molecular modeling and complete lineshape analysis indicated a four site exchange process for which free energies of activation and free energies could be established. ΔG values for the barriers of rotation are in the range of 57–59 kJ · mol − 1 at 273 K, which is unusually high for an unsubstituted phenyl group. Received May 3, 2001. Accepted (revised) June 8, 2001  相似文献   

6.
Synthesis of “Inorganic” Pode-type Molecules. II The reaction of the amino compounds MeyB? NMe2 (B ? As, y ? 2; B ? Si, y ? 3) with 1, n-dioles results in the formation of the compounds HO(CH2)nOBMey. These compounds can be used as the arms of pode-type molecules MexA[? O(CH2)nOBMey]z with A ? Si, As. The influence of A, B, n, and z in the rearrangement of these molecules is examined. A second type of pode molecules can be prepared by the reaction of Me2As? R? OH (R ? CH2CH2, CH2CH2(OCH2CH2)2) with the amino compounds Mex(NMe2)z (A ? As, Si). These reactions result in the formation of molecules as MexA(ORAsMe2)z.  相似文献   

7.
Summary.  The polymeric compound [Ru(cod)Cl2] x (cod = cyclooctadiene) reacts with 2 equivalents of tmeda (N,N,N′,N′-tetramethylethylenediamine) in refluxing MeOH to afford trans-[Ru(cod)(tmeda)(Cl)(H)] (1), which upon treatment with CHCl3 is readily converted to the dichloro complex trans-[Ru(cod)(tmeda)Cl2] (2). When [Ru(cod)Cl2] x is reacted with tmeda under an atmosphere of H2 (3 bar), the bis-tmeda complex trans-[Ru(tmeda)2Cl2] (3) is obtained in 80% yield. DFT calculations revealed that 3 is by 52 kJ/mol more stable than the corresponding cis isomer. Attempts to prepare the coordinatively unsaturated complex [Ru(tmeda)2Cl]+ by reacting 1 with TICF3SO3 were unsuccessful. According to DFT calculations, however, such a complex should be stable and, interestingly, should adopt a square pyramidal rather than a trigonal bipyramidal structure. If halide abstraction of 3 is performed in the presence of terminal alkynes HC*CR (R*t-Bu, n-Bu), the cationic vinylidene complexes [Ru(tmeda)2(Cl)(*C*CHR)]+ (4a,b) are obtained. Received March 26, 2001. Accepted April 26, 2001  相似文献   

8.
Summary.  The complexes RuTp(cod)X (X = Br (2), I (3), CN (4)) have been obtained by the reaction of RuTp(cod)Cl (1) with KX in boiling MeOH in high yields. The cationic complexes [RuTp(cod)(py)]+ (5), [RuTp(cod)(dmso)]+ (6), and [RuTp(cod)(CH3CN)]+ (7) were prepared as the CF3SO3 salts by reacting 1 with 1 equivalent of AgCF3SO3 in the presence of the respective co-ligand in CH2Cl2. The crystal structures of 1, 3, 4, 5, 6, and 7 are reported. Structural features are discussed in conjunction with 1H, 13C, and 15N NMR spectroscopic data revealing a linear correlation of 15N chemical shifts and Ru-N (trans to X(L)) bond distances. Received August 31, 2000. Accepted (revised) October 23, 2000  相似文献   

9.
Summary Solid complexes of 3-acetyl-1,5-diaryl and 3-cyano-1,5-diaryl formazans were prepared and characterized by elemental analysis, IR, NMR, TGA and DTA analyses. Based on these studies, the suggested general formula for the complexes is [M(HL) m (OH) n or (NO 3 or Cl) x ·(H2O) y or (C2H5OH orDMSO) z , where HL=formazanM=Ce3+, Th4+, and UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 andz=0–3. The metal ions are expected to have coordination numbers 6–8.
Strukturuntersuchungen an 3-Acetyl-1,5-diaryl- und 3-Cyan-1,5-diaryl-formazan-Chelaten mit Cer(III), Thorium(IV) und Uran(VI)
Zusammenfassung Die hergestellten Chelate wurden mittels Elementaranalyse, IR, NMR, TGA und DTA charakterisiert. Darauf basierend wird die generelle Formel [M(HL) m (OH) n bzw. (NO 3 oder Cl) x ·(H2O) y oder (C2H5OH bzw.DMSO) z ] vorgeschlagen, wobei HL=Formazan,M=Ce3+, Th4+ oder UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 undz=0–3. Die Metallionen haben Koordinationszahlen von 6–8.
  相似文献   

10.
 The polymeric compound [Ru(cod)Cl2] x (cod = cyclooctadiene) reacts with 2 equivalents of tmeda (N,N,N′,N′-tetramethylethylenediamine) in refluxing MeOH to afford trans-[Ru(cod)(tmeda)(Cl)(H)] (1), which upon treatment with CHCl3 is readily converted to the dichloro complex trans-[Ru(cod)(tmeda)Cl2] (2). When [Ru(cod)Cl2] x is reacted with tmeda under an atmosphere of H2 (3 bar), the bis-tmeda complex trans-[Ru(tmeda)2Cl2] (3) is obtained in 80% yield. DFT calculations revealed that 3 is by 52 kJ/mol more stable than the corresponding cis isomer. Attempts to prepare the coordinatively unsaturated complex [Ru(tmeda)2Cl]+ by reacting 1 with TICF3SO3 were unsuccessful. According to DFT calculations, however, such a complex should be stable and, interestingly, should adopt a square pyramidal rather than a trigonal bipyramidal structure. If halide abstraction of 3 is performed in the presence of terminal alkynes HC*CR (R*t-Bu, n-Bu), the cationic vinylidene complexes [Ru(tmeda)2(Cl)(*C*CHR)]+ (4a,b) are obtained.  相似文献   

11.
Summary.  Carbonyl compounds of the type XPhCOR (R = H, Me, Ph; X = H, Me, Cl, Br) are prepared in high yields by reaction of the corresponding benzylic alcohols XPhCHOHR with KNa4 [Ag(HIO6)2]×12H2O in alkaline solution. This method allows the selective oxidation of benzylic alcohols in compounds containing other types of alcoholic functional groups. Received January 18, 2000. Accepted (revised) February 23, 2000  相似文献   

12.
A kinetic-potentiometric method is described for the quantitative assay of formaldehyde (HCHO) in pharmaceutical and industrial preparations. It is based on the reaction of HCHO with (ethylenediamine)-Cu(II)-sulfate [Cu(CH2NH2)2(H2O)2] · SO4. The changes in potential, resulting from the release of the Cu(II) cations, are monitored with a Cu(II)-ion selective electrode. The calibration curve for the HCHO is linear in the concentration range 50–250 mg L−1, with a limit of detection of 8.5 mg L−1. The method shows very good reproducibility with an RSD of 2.6% for successive injections (n = 5) of 150 mg L−1 HCHO primary solution, while it is interference free. The method was successfully tested in various industrial and pharmaceutical preparations.  相似文献   

13.
A method was developed for the determination of metal complexes with glycine (glycinates, [M(Gly)x(H2O)y(SO4)z]n, where M denotes Zn, Cu, Mn and Fe) in premix samples used for the preparation of animal feeds enriched in essential trace elements. The method was based on the extraction of the glycinates with 10 mM ammonium acetate (pH 7.4) followed by their determination using capillary electrophoresis with ICP MS detection. The stability of the glycinates in solution was verified by electrospray TOF-MS. Each supplement was shown to be a mixture of complexes, with polymerization degrees ranging from n = 1 to n = 4 (depending on the metal), that were fully or partially dehydrated. The metal glycine complex moiety was found to be preserved during capillary electrophoresis. The detection limits, calculated as three times the standard deviation of the blank plus the blank, were between 0.05 and 0.2 μg mL−1 (as the metal), and the calibration curves were linear, allowing the analysis of premix samples. Repeatability for glycinate standards was below 12%, and analytical precision was typically within 15%.  相似文献   

14.
Several solid phases with the general formula xM[XHgSO3yHgX2·zMX·nH2O were obtained from aqueous solutions during phase formation studies in the systems M2SO3/HgX2 (M = NH4, K; X = Cl, Br). All phases were structurally characterized on the basis of single crystal X‐ray diffraction data and adopt new structure types. Compounds with x, y, z = 1 and n = 0 are isostructural (structure type I ) and crystallise with two formula units in space group P21/m and lattice parameters of a ≈ 9.7, b ≈ 6.2, c ≈ 10.4Å, β ≈ 111°. Compounds with x, y = 1 and z, n = 0 (structure type II ) crystallize in space group Cmc21 with four formula units and lattice parameters of a ≈ 5.9, b ≈ 22.0, c ≈ 6.9Å. The structures with x = 2, y, z = 1 and n = 0 are likewise isostructural (stucture type III ) and consist of four formula units in space group Pnma with lattice parameters of a ≈ 22.2, b ≈ 6.1, c ≈ 12.4Å. K[HgSO3Cl]·KCl·H2O is the only representative where x = 1, y = 0, z = 1 and n = 1 (structure type IV ). It is triclinic (space group ) with four formula units and lattice parameters of a = 6.1571(8), b = 7.1342(9), c = 10.6491(14) Å, α = 76.889(2), β = 88.364(2), γ = 69.758(2)°. Characteristic for all structures types is the segregation of the M+ cations and the anions and/or HgX2 molecules into layers. The [XHgSO3] anions are present in all structures and have m symmetry, except for K[HgSO3Cl]·KCl·H2O with 1 symmetry (but very close to m symmetry). The different [XHgSO3] units exhibit very similar Hg‐S distances (average 2.372Å) and are more or less bent with ∠(X‐Hg‐S) angles ranging from 159.7 to 173.7°. The molecular HgX2 entities present in structure types I ‐ III deviate only slightly from linearity with ∠(X‐Hg‐X) angles ranging from 174 to 179°. The structures are stabilised by interaction of the K+ or NH4+ cations that are located between the anionic layers or in the vacancies of the framework, by K‐O contacts or, in case of ammonium compounds, by medium to weak hydrogen bonding interactions of the type N‐H···O.  相似文献   

15.
Summary.  The solid-state tautomerization of the hydrido-alkynyl derivatives [Cp *RuH(C&*CR)-(dippe)][BPh4] (Cp* = C5Me5; R = SiMe3, Ph, H; dippe = 1,2-bis-(diisopropylphosphino)-ethane) to their vinylidene isomers [Cp *Ru*C*CHR(dippe)][BPh4] was studied by IR spectroscopy. Characteristic isothermic αvs. t curves for each individual rearrangement process were recorded. Their shape, and hence the isomerization mechanism, depends strongly on the nature of the substituent R. The kinetic analysis of the above curves using the Avrami-Erofeev provided some mechanistic information about the isomerization process in the solid. Received July 7, 2000. Accepted August 29, 2000  相似文献   

16.
The composition of mixed-ligand complexes of cerium (III) and europium (III) acetates and pivalates with monoethanolamine (MEA) depends on the synthesis conditions and the nature of carboxylate ligand. We prepared solid complexes [Ln(Piv)3(MEA) x ], where Ln = Ce, Eu; HPiv-2,2-dimethylpropionic (pivalic) acid; x = 1, 1.5, and gel-like hydroxocomplexes [Ln(Carb) nxy ,(NO3) x (OH) y (MEA) w (H2O) z ], where Ln = Ce, n = 4; Ln = Eu, n = 3; HCarb is acetic acid (HAcet) or HPiv. The values of the coefficients x, y, w, and z depend on the synthesis conditions and heat treatment. Prepared compounds were characterized by IR and 1H NMR spectroscopies, elemental and thermal analyses, and MALDI-MS. The ESI-MS method was used to characterize the processes occurring in the solutions.  相似文献   

17.
Reaction of [Ru6C(CO)16]2− with an excess of AgX (X = Cl, Br or I) affords heteronuclear clusters of formula [{Ru6C(CO)16Ag2X}2]2− in 80% yield, which for X = I and X = Br/Cl were crystallographically characterised. The formation of the cluster was followed in solution using electrospray ionisation mass spectrometry (ESI-MS), which revealed the presence of a wide range of clusters with the general formula [{Ru6C(CO)16} x Ag y X z ](2x−y+z)− where x = 1 or 2, y = 1, 2, 3 or 4 and z = 0, 1 or 2. The high yield of the product despite the evident complicated solution speciation is attributed to selective crystallisation of the observed compound driving the equilibrium toward this product.  相似文献   

18.
Fluoroalkyl end-capped cooligomers having adamantane as a pendant group [RF-(Ad-HAc) x –(Co-M) y -RF] were prepared by the reactions of fluoroalkanoyl peroxide with 3-hydroxy-1-adamantylacrylate (Ad-HAc) and comonomers (Co-M) such as acrylic acid (ACA), N,N-dimethylacrylamide (DMAA), and acryloylmorpholine (ACMO) under mild conditions. Thermogravimetric analyses (TGA) showed that thermal stability of RF-(Ad-HAc) x –(Co-M) y -RF was superior to that of the corresponding fluoroalkyl end-capped cooligomers having adamantane in the main chains [RF-(Ad) x –(Co-M) y -RF] and the fluoroalkyl end-capped homooligomers possessing no adamantyl segments [RF-(M) n -RF]. It is interesting to note that fluoroalkyl end-capped Ad-Hac–DMAA cooligomer [RF-(Ad-HAc) x –(DMAA) y -RF] was found to form the nanometer size-controlled cooligomeric aggregates which consist of around 16 fluorinated cooligomeric molecules in methanol/water mixed solvents. Furthermore, these fluorinated cooligomeric aggregate could occupy around 320 ADMDD [5-(2-adamantylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione] molecules as guest molecules per aggregate core, although ADMDD could not be encapsulated into the RF-(Ad) x –(Co-M) y -RF cooligomeric and RF-(M) n -RF homooligomeric aggregate cores under similar conditions.  相似文献   

19.
The electron projection function P(x, z) = ∫ ρ(x, y, z) dy is used to evaluate charge transfer and covalency in two series of molecules, LiX and CH3X (X = Li, BeH, BH2, CH3, NH2, OH, and F), with wavefunctions derived from STO-3G, 4-31G, and, in some cases, 6-31* ab initio calculations. The precision of the method and comparison with Mulliken populations analysis are described. Particular attention is given to CH3Li which by our criteria is wholly ionic.  相似文献   

20.
Carbonylrhodium complexes formed during hydroformylation of CH2O from various rhodium precursors were investigated byin situ IR spectroscopy. It was found that under the conditions of the hydroformylation of CH2O inN,N-dimethylacetamide (DMAA), RhH(CO)(PPh3)3, RhCl(CO)(PPh3)2, RhCl(PPh3)3, RhCl(CO)(PBu3)2, and [RhCl(CO)2]2 form complex systems that necessarily contain anionic complexes, [Rh(CO)2Lx(DMAA)y] (L = PPh3, PBu3,x = 1 to 2,y = 1 to 0; [Rh(CO)4]). The participation of ionic structures in the hydroformylation of CH2O, most likely, in the step of the activation of CH2O, was proven by kinetic techniques.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1066–1069, June, 1995.  相似文献   

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