Dark brown single crystals of [Ag(NH3)2]Ag(OsO3N)2 were obtained from the reaction of Ag2CO3, OsO4, and NH3 in aqueous solution. The crystal structure was solved in the monoclinic space group C2/m, with the following unit-cell dimensions: a=1962.5(3), b=633.1(1), c=812.6(1) pm, β=96.71(1)°. The final reliability factor was R=0.0256 for 1034 reflections with I>2σ(I). Linear [Ag(NH3)2]+ ions are present oriented perpendicular to the [010] direction, leading to short Ag+-Ag+ distances of 316 pm. A second type of Ag+ ions in the crystal structure present coordination number “6+1” and are surrounded by oxygen and nitrogen atoms of the nitridoosmate groups. Within the first of the two crystallographically distinguishable anions one can clearly differentiate between oxygen and nitrogen atoms while the second one exhibits a N/O disorder over two positions. The infrared spectrum of [Ag(NH3)2]Ag(OsO3N)2 shows the typical absorptions which can be attributed to the complex anions and the NH3 ligands. 相似文献
The metastability of oxygen paramagnetic centres adsorbed on a metallic oxyde has been pointed out. An energetic pattern is given and the energy values are measured. Various considerations on the density of paramagnetic centres and their probable association with a defect are presented. 相似文献
The second-order rate constants of gas-phase Lu(2D3/2) with O2, N2O and CO2 from 348 to 573 K are reported. In all cases, the reactions are relatively fast with small barriers. The disappearance rates are independent of total pressure indicating bimolecular abstraction processes. The bimolecular rate constants (in molecule−1 cm3 s−1) are described in Arrhenius form by k(O2)=(2.3±0.4)×10−10exp(−3.1±0.7 kJmol−1/RT), k(N2O)=(2.2±0.4)×10−10exp(−7.1±0.8 kJmol−1/RT), k(CO2)=(2.0±0.6)×10−10exp(−7.6±1.3 kJmol−1/RT), where the uncertainties are ±2σ. 相似文献
Thin polycrystalline copper films are deposited in a special UHV cell on glass substrates and are covered step by step with CO2. The optical and electrical properties of the films are studied in-situ by means of ellipsometry and resistivity measurements. The properties of the clean films correspond to literature data. In the case of monolayer adsorption of CO2, the changes in the ellipsometrical angles are +1° and +0.1°, similar to the Cu/O and Cu/CO systems. Three-dimensional island growth leads to a drastical increase of and by several orders of magnitude. The resistivity first quickly decreases and then slowly reapproaches the initial value. This marked kinetics is quantitatively interpreted on the basis of a diffusion model. 相似文献
IR spectra of oxygen adsorbed on SnO2 with and without lattice defects have been studied. At low temperatures oxygen is adsorbed on defect SnO2 in two forms of O
2–
. This supports the earlier results obtained by ESR. The low-temperature forms of adsorbed oxygen (unrevealed in ESR spectra) were detected on defectless SnO2. High-temperature forms of adsorbed oxygen appear in the IR-spectra as bands due to vibrations of the cation-oxygen bond.
Molecular beam deflection studies on (CO2)2 and (OCS)2 indicate that both these species are polar molecules. Structural implications of this are explored in light of previous studies of these systems. 相似文献
A new layered indium-organic framework material, In[NC5H3(CO2)2](OH2)F has been synthesized by a hydrothermal reaction using In2O3, NH4F, 2,6-NC5H3(CO2H)2 (2,6-pyridinedicarboxylic acid), HF, and water at 200 °C. Single-crystal X-ray diffraction was used to determine the structure of the reported material. In[NC5H3(CO2)2](OH2)F has a novel layered structure consisting of InO5NF polyhedra and the pyridinedicarboxylate organic linker. Detailed structural analyses with full characterization including infrared spectrum, thermogravimetric analysis, elemental analysis, exchange reactions for the coordinated water molecule, and gas adsorption experiments are reported. 相似文献
The reactions of (CO2)2 and (SO2)2 with Ba have been investigated using a crossed beam arrangement and the laser-induced fluorescence technique. Internal energy in the BaO product was probed in order to study differences between monomeric and dimeric reactions. The reaction cross section for the dimers of CO2 was found to be between four and eightfold larger than that of the monomers. This can be explained by the change in the reaction mechanism due to the positive electron affinity of the dimers versus the negative electron affinity of the monomers. The product BaO from the dimeric reactions is much colder rotationally than in the monomeric case. This phenomenon can be explained based on the kinematics. 相似文献
La2(CO3)3 nanowires were prepared in the nonionic surfactant microemulsion(Triton X-100/cyclohexane/water)system. Transmission electron microscopy (TEM) and selected area electronic diffraction (SAED) were used to characterize the shape and size of the products. The results showed that the pH value and concentration of mother solution, temperature and aging time all could affect the morphology and size of the La2(CO3)3 nanowires. The lengths of the nanowires were more than 10 μm and the diameters were in the range of 30～200 nm. 相似文献
Bi2Mo3O12 is a selective oxidation catalyst of propylene into acrolein. Surface potential measurements proved the presence of an equilibrium between gaseous oxygen and the O2– species adsorbed on the surface of the catalyst, under oxygen atmosphere, in the range 538K–673K. This is in accordance with the fact that O2– is a selective oxidation species. An oxygen adsorption mechanism is also discussed.
The vibrational relaxation time for CO2(v3) + O(3P) has been measured by laser fluorescence. The observed value, βCO2.O = 0.21 ± 0.04 μsec, is an order of magnitude lower than the relaxation time for self-collisions. 相似文献
The iridium(I) complex [Ir(CO2Me)(CO)2(PPh3)2] undergoes a transesterification reaction with the alcohols CH2C(R)CH2OH (R = H, Me), MeCCCH2CH2OH, and HOCH2CH2OH to afford the complexes [Ir(CO2CH2CH2CMe)(CO)2(PPh3)2] and [Ir(CO2CH2CH2OH)(CO)2(PPh3)2], respectively. In contrast the acetylenic alcohol HCCCH2CH2OH gives [Ir(CCCH2CH2OH)(CO)PPh3)2]. Some reactions of the new complexes are described. 相似文献
The rate constant for collisional deactivation of CO2(0001) in pure CO2 has been measured at room temperature using the laser fluorescence technique. The relaxation rate has been found to be (1.0 ± 0.2) × 10?14 cm3 s?1 which is in favorable agreement with previously published values. 相似文献
