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1.
The mass spectra of the following acetylenic derivatives of iron, ruthenium and osmium carbonyls are reported: the iron compounds Fe2(CO)6[C2(C6H5)s2]2, Fe2(CO)6[C2(CH3)2]2 and Fe2(CO)6[C2(C2H5)2]2, the ruthenium compounds Ru2(CO)6[C2(C6H5)2]2, and Ru2(CO)6[C2(CH3)2]2 and the osmium compounds Os2(CO)6[C2(C6H5)2]2, Os2(CO)6[C2HC6H5]2 and Os2(CO)6[C2(CH3)2]2. Iron compounds exhibit breakdown schemes where binuclear, mononuclear and hydrocarbon ions are present. On the other hand, ruthenium and osmium compounds fragment in a similar way and give rise to singly and doubly charged binuclear ions. Phenylic derivatives of ruthenium and osmium also give weak triply charged ions. The results are discussed in terms of relative strengths of the metal-metal and metal-carbon bonds.  相似文献   

2.
On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.  相似文献   

3.
The depression of freezing point of molten K2Cr2O7 and KNO3 as solvents was measured after addition of small concentrations of the following compounds: to K2Cr2O7: MoO3, CrO3, (NH4)2CrO4, K2MoO4, Na2MoO4, Li2MoO4, and Na2Mo2O7, respectively; to KNO3: CrO3, (NH4)2Cr2O7 K2Cr2O7, K2CrO4 and MoO3, (NH4)6(Mo7O24) · 4 H2O, K2Mo2O7, K2MoO4, Na2MoO4 and Li2MoO4, respectively. It could be concluded from the measured values of the freezing point depression if a reaction between solvent and solute took place.  相似文献   

4.
Reactions of CrO2F2 with MF or MF2 gave the corresponding M2CrO2F4 and MCrO2F4 fluorochromates. With the Lewis Acids (SO3, TaF5, SbF5) and (CF3CO)2O known and new chromyl compounds [CrO2(CF3COO)2, CrO2(SO3F)2, CrO2FTaF6, CrO2FSbF6, CrO2FSb2F11] were produced. Chromyl fluoride and inorganic salts (CF3COONa and NaNO3) produced the following complexes - Na2CrO2F2(CF3COO)2 and Na2CrO2F2(NO3)2. Unusual solid products were obtained with CrO2F2 and NO, NO2, SO2.A new method of preparing CrO2F2 is also presented.  相似文献   

5.
The triphenylsiloxy-substituted cyclotriphosphazenes, N3P3Cl5OSiPh3, gem-N3P3Cl4(OSiPh3)2, N3P3(OSiPh3)6, and N3P3(OPh)5OSiPh3, have been prepared. The synthesis of gem-N3P3Cl4(OSiPh3)2 involves the reaction of (NPCl2)3 with Ph3SiONa to form the intermediates gem-N3P3Cl4(OSiPh3)2(ONa) and gem-N3P3Cl4(ONa)2, which yield gem-N3P3Cl4(OSiPh3)2 when treated with Ph3SiCl. The compounds N3P3Cl5OSiPh3 and N3P3(OSiPh3)0 are formed by the condensation reactions of N3P3Cl5OBun and N3P3(OBun)6, respectively, with Ph3SiCl. The compound N3P3(OPh)5OSiPh3 is synthesized by the reaction between N3P3(OPh)5Cl and Et3SiONa to first give the intermediate N3P3(OPh)5ONa, which yields N3P3(OPh)5OSiPh3 when reacted with Ph3SiCl. The structural characterization and properties of these compounds are discussed. The crystal and molecular structure of gem-N3P3Cl4(OSiPh3)2 has been investigated by single-crystal X-ray diffraction techniques. The crystals are monoclinic with the space group P21/c with a = 16.850(8), b = 12.829(4), c = 18.505(15) Å, and β = 101.00(6)° with V = 3927 Å3 and Z = 4. © 1996 John Wiley & Sons, Inc.  相似文献   

6.
Reactions of R4Sb2 (R = Me, Et) with (Me3SiCH2)3M (M = Ga, In) and Crystal Structures of [(Me3SiCH2)2InSbMe2]3 and [(Me3SiCH2)2GaOSbEt2]2 The reaction of (Me3SiCH2)3In with Me2SbSbMe2 gives [(Me3SiCH2)2InSbMe2]3 ( 1 ) and Me3SiCH2SbMe2. [(Me3SiCH2)2GaOSbEt2]2 ( 2 ) is formed by the reaction of (Me3SiCH2)3Ga with Et2SbSbEt2 and oxygen. The syntheses and the crystal structures of 1 and 2 are reported.  相似文献   

7.
The Sulfenic Fluorides CF3SF and CF2CISF and their Dimers The reactions of RfSCl (Rf = CF3, CF2Cl) with HgF2 and AgF give RfSF and the dimer product RfSF2SRf in high yield and various ratios, in contrast, activated KF leads only to RfSF in low yield. A complex of transition metal and sulfenic halide as an intermediate step is discussed for the dimerisation. As liquid CF3SF2SCF3 disproportionates into CF3SF3 and CF3SSCF3 and the hydrolysis of CF3SF2SCF3 gives the stable compound CF3S(O)SCF3 · PF3 reacts with RfSF as well as with RfSF2SRf to RfSPF4. The products of the spontaneous decomposition of CF2ClSF were investigated. I.r., n.m.r., and mass spectra are reported and discussed. It was possible to carry out vapour pressure measurements of CF2ClSF.  相似文献   

8.
The Formation of Disilylphosphino-Element Compounds of C, Si, P The reactions of (me3Si)2PLi · OR2 a (OR2 = 1 monoglyme or 2 THF; me = CH3) with CH3Cl, CH2Cl2, ClCH2CH2Cl and ClCH2? C6H5 give the compounds (me3Si)2Pme, (me3Si)2P? CH2? P(Sime3)2, (me3Si)2P? CH2CH2Cl, (me3Si)2P? CH2CH2? P(Sime3)2 and (me3Si)2P? CH2C6H5 respectively. In the same manner a reacts with me2SiCl2 in a molar ratio 1:1 to (me3Si)2P? Sime2Cl and in a molar ratio 2:1 to (me3Si)2P? Sime2? P(Sime3)2 b . The compound b decomposes to [me3SiP? Sime2]2 and (me3Si)3P at 220°C. In the reactions of a with ClP(C6H5)2 and ClPme2 the compounds (me3Si)2P? P(C6H5)2 and (me3Si)2P? Pme2, respectively, are obtained. a reacts with HgCl2 to (me3Si)2P? P(Sime3)2. (me3Si)3P can be cleaved with ClP(C6H5)2 and ClPme2 yielding (me3Si)2P? P(C6H5)2 and (me3Si)2P? Pme2, respectively. The 1H- and 31P-n.m.r. and mass spectroscopic data are reported.  相似文献   

9.
Contributions to the Investigation of Inorganic Non-stoichiometric Compounds. XXXIII. Preparation and Electron Microscopical Investigation of Hf2Nb20O54, M3Nb44O116, and MNb24O62 (M = Zr, Hf) The phases Hf2Nb20O54, Zr3Nb44O116, Hf3Nb44O116, and β-HfNb24O62 have been prepared for the first time. The oxides MO2 (M = Zr, Hf) and Nb2O5 were fused with (NH4)2SO4 and their mixed precipitations were heated at 1350°C. In the same way we also obtained pure β-ZrNb24O62. The new compounds have block structures, as the structure investigation with HRTEM shows. Hf2Nb20O54 is isostructural with Nb22O54, the same is valid for Zr3Nb44O116 and Hf3Nb44O116 with respect to Nb47O116. β-HfNb24O62 has the same structure as β-ZrNb24O62 and β-Nb25O62.  相似文献   

10.
Reactivity, in the solid state between Ag2S and Ag2CrO4, was investigated by DTA, XRD and IR methods. It was found that, according to a composition of an initial Ag2S/Ag2CrO4 mixture, the products of a reaction of Ag2S with Ag2 CrO4 can be: solid solution with Ag2CrO4 structure (Ag2Cr1–xSxO4) and AgCrO2; or solid solution Ag2Cr1–xSxO4, Ag2SO4, AgCrO2 and metallic silver; or Ag2S, β-Ag8S4O4, Ag, AgCrO2, Ag2SO4 and Ag2Cr1–xSxO4 solid solution. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

11.
The phase diagrams of four binary systems (C10H21NH3)2CoCl4?(C16H33NH3)2CoCl4, (C12H25NH3)2CoCl4?(C16H33NH3)2CoCl4, (C10H21NH3)2ZnCl4?(C16H33NH3)2ZnCl4 and (C12H25NH3)2ZnCl4?(C16H33NH3)2ZnCl4 were investigated by means of DSC. These six compounds and their binary mixtures can retain energies between 74 and 115 J/g during solid-state transformations at temperatures between 70 and 105°C, and they are therefore being considered for potential use in solar energy systems.  相似文献   

12.
Contributions to the Chemical Transport of Metal Oxides. V. Transport of Ternary and Quaternary Mixed Ferrites by their Chlorides The transport by means of HCl as transporting gas in a closed system in the case of the ternary mixed ferrites (Ni0,8Fe2,2O4, Mn0,75Fe2,25O4, Mn1,286Fe1,714O4) and the quaternary mixed ferrites (Mg0,5Mn0,5Fe2O4, Mg0,75Mn0,536Fe1,714O4, Mg0,281Mn0,469Fe2,25O4, Mn0,5Zn0,5Fe2O4, Mn0,5Zn0,45Fe2,05O4, Ni0,5Zn0,5Fe2O4) between T2 = 1100?1000°C and T1 = 1000?800°C was investigated. Transported crystals were characterized by chemical analysis and the saturation magnetization, the transport rate has been checked. In the case of Mn0,5Zn0,45Fe2,05O4 two phases were transported. By discussing the phase diagram an explanation is given.  相似文献   

13.
Reaction of Tin Chlorides with Polysulfides. Crystal Structures of (PPh4)2[SnCl2(S6)2], (PPh4)2[Sn4Cl4S5(S3)O], and (PPh4)2[SnCl6] · S8 · 2CH3CN . The reaction of PPh4[SnCl3] with Na2S4 in acetonitrile in the presence of small amounts of water yields (PPh4)2[Sn4Cl4S5(S3)O] and minor amounts of (PPh4)2[SnCl2(S6)2], PPh4Cl · 2S8 and (PPh4)2[SnCl6]. SnCl4 is partially reduced by (PPh4)2Sx, PPh4[SnCl3] and (PPh4)2[SnCl6] · S8 · 2CH3CN being produced. According to the X-ray crystal structure determination the [Sn4Cl4S5(S3)O]2?-ion consists of an O atom that is coordinated by four Sn atoms which in turn are liked with one another by five single S atoms and one S3 group. In the [SnCl2(S6)2]2?-ion the Sn atom is octahedrally coordinated by two Cl atoms in trans arrangement and by two chelating S6 groups. Octahedral [SnCl6]2? ions and S8 molecules in the crown conformation are present in (PPh4)4[SnCl6] · S8 · 2CH3CN.  相似文献   

14.
通过高温固相法对醋酸镧(C6H9O6La·xH2O)与高钼酸铵((NH46Mo7O24·4H2O)在一定条件下热解制备非Pt催化剂La2Mo2O7(La2O3-2MoO2)。进一步采用2种方法将La2Mo2O7与多壁碳纳米管(MWCNTs)进行复合,一种是将La2Mo2O7喷涂到MWCNTs表层之上得到La2Mo2O7/MWCNTs,另一种是将两者均匀混合掺杂得到La2Mo2O7@MWCNTs,再将上述2种复合材料应用于染料敏化太阳能电池对电极进行相应研究。通过扫描电子显微镜(SEM)表征了复合催化材料的微观形貌,X射线衍射(XRD)确定了微观结构。采用电流密度-光电压曲线、循环伏安,交流阻抗以及塔菲尔极化分析了材料的光电性能。实验结果表明在电解液I3-/I-中,基于La2Mo2O7/MWCNTs与La2Mo2O7@MWCNTs的对电极,相同的条件下在光电池中获得的光电转换效率分别为6.09%和4.84%,明显高于MWCNTs的3.94%和La2Mo2O7的0.87%。电极性能的提高可归因于La2Mo2O7复合催化剂相对大的比表面积和高导电性。  相似文献   

15.
Coexistence Relations, Preparation and Properties of Ternary Compounds in the System Cu/Mo/O The phase diagram of the ternary system Cu/Mo/O is presented at 773 K. The compounds CuMoO4, Cu3Mo2O9, Cu4Mo5O17, Cu6Mo5O18, Cu4–xMo3O12, and CuxMoO3 are found to be thermodynamical stable. The homogeneity range of Cu4–xMo3O12 runs to x = 0.1–0.2. Single crystals of CuMoO4 and Cu3Mo2O9 were grown by chemical transport reactions with TeCl4, Cl2, HCl, and Br2 as transport agent. The results were compared with thermochemical calculations. The decomposition of CuMoO4 and Cu3Mo2O9 was investigated with thermal analysis and decompositon pressure measurements.  相似文献   

16.
The cloud points (CPs) of the copolymers 17R4 and L64 were first measured, and then the effects of salts ((NH4)3C6H5O7, K3C6H5O7) on 17R4 and L64 were researched. After finishing the work described above, the temperature (278.15, 283.15, and 288.15) K of aqueous two-phase systems was determined, which consist of 17R4-(NH4)3C6H5O7, 17R4-K3C6H5O7, L64-(NH4)3C6H5O7, and L64-K3C6H5O7. Finally, the liquid–liquid equilibrium (LLE) data of binodal curve and the tie line for 17R4-(NH4)3C6H5O7 aqueous two- phase systems (ATPSs) 17R4-K3C6H5O7 ATPSs, L64-(NH4)3C6H5O7 ATPSs, and L64-K3C6H5O7 ATPSs were obtained. Nonlinear fitting of the empirical equation was used for making the diagram. The results showed that the change in the size of the two-phase areas increases with the increase of temperature. The capacity of the salts to induce phase segregation follows the Hofmeister series, that is, K3C6H5O7?>?(NH4)3C6H5O7. In addition, the findings also showed that the phase separation ability of 17R4 is better than that of L64.  相似文献   

17.
Reactivity in the solid state between CoWO4 and some rare-earth metal tungstates RE2WO6 (RE = Sm, Eu, Gd) was investigated by the XRD method. Two families of new isostructural cobalt and rare-earth metal tungstates, Co2RE2W3O14 and CoRE4W3O16, were synthesized. The Co2RE2W3O14 phases are formed by heating in air the CoWO4 and RE2WO6 compounds mixed at the molar ratio 2:1, while the CoRE4W3O16 phases are synthesized at the molar ratio of CoWO4/RE2WO6 equals to 1:2. The Co2RE2W3O14 phases as well as the CoRE4W3O16 compounds crystallize in the orthorhombic system. The Co2RE2W3O14 and CoRE4W3O16 compound melt above 1150 °C. A melting manner of the Co2RE2W3O14 and CoRE4W3O16 compounds was determined in an inert atmosphere. The formation of CoWO4−x phase was observed during heating in an inert atmosphere.  相似文献   

18.
Phase ratios in the three-component oxide system K2O-V2O4-SO3 in the region of the sulfur trioxide concentrations corresponding to its concentrations in the active component of vanadium catalysts for SO2 to SO3 conversion have been studied using powder X-ray diffraction, IR spectroscopy, microscopy, and chemical analysis. Four individual compounds (K2VO(SO4)2, K2(VO)2(SO4)3, K2VO(SO4)2S2O7, and K2(VO)2(SO4)2S2O7) and K2(VO)2(SO4)2S2O7 and VOSO4-base solid solutions of composition K2(VO)2+x (SO4)2+x S2O7 (0 ≤ x ≤ 1.5) were found in the system. K2VO(SO4)S2O7 and K2(VO)2(SO4)2S2O7 lose their sulfur trioxide when heated above 350°C under an inert atmosphere, and convert to K2VO(SO4)2 and K2(VO)2(SO4)3, respectively. This implies that K2VO(SO4)2S2O7 and K2(VO)2(SO4)2S2O7, as well as K2(VO)2+x (SO4)2+x S2O7 solid solution, cannot exist in the active component of real industrial catalysts.  相似文献   

19.
Preparation, Properties and Vibrational Spectra of K[SbCl5N3], K[SbCl5NCO] and K[SbCl5CN]. KaN3, KNCO and KCN react in liquid SO2 with stoichiometric amounts of SbCl5 yielding K[SbCl5N3] K[SbCl5NCO], and K[SbCl5CN], respectively. NaN3 and SbCl5 form Na[SbCl5N3] which contains impurities of Na[SbCl6]. With more SbCl5 (SbCl4N3)2 is obtained from K[SbCl5N3] and (SbCl4NCO)2 from K[SbCl5NCO], [BCl2N3]3 is formed from K[SbCl5N3] and BCl3. The vibrational spectra of the pentachloro-pseudohalo-antimonates can be assigned with a model of C4v symmetry for the direct neighborhood of the Sb atoms.  相似文献   

20.
Co3O4/γ-Al2O3 catalysts with variable Co3O4 loadings (5–20 wt%) and deposition of 15% Co3O4 on La2O3/γ-Al2O3 were prepared by wet impregnation method. La2O3-γ-Al2O3 support with variable composition of La2O3 (2–6 wt%) were prepared by co-precipitation method. All the catalysts were tested for oxidative dehydrogenation of ethylbenzene with CO2 as soft oxidant. Among the Co3O4/γ-Al2O3 catalysts, 15% Co3O4/γ-Al2O3 has shown good performance and hence this catalyst has been chosen to investigate the effect of La2O3 species. CO2 pulse chemisorption data indicate more amount of CO2 uptake over 15% Co3O4/4%La2O3/γ-Al2O3 catalyst which clearly indicates that this catalyst exhibits good performance in ethylbenzene dehydrogenation with CO2 as soft oxidant because of reverse water gas shift reaction. Temperature programmed reduction studies indicate that the Co3O4 catalysts follow two step reduction mechanism from Co3O4 to CoO and then to Co and La2O3 promotional effect is visible through facile reduction of Co3O4 species. La2O3 doping has a vital influence in getting enhanced ethylbenzene conversion, styrene yield and alleviates catalyst deactivation compared to that of unpromoted Co3O4/γ-Al2O3 catalyst. TGA studies indicate the presence low amount coke deposition during time-on-stream over 15% Co3O4/4%La2O3/γ-Al2O3 catalyst compared to 15% Co3O4/γ-Al2O3 catalyst.  相似文献   

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