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351.
The Novel cis‐[Bi3I12]3?‐Anion in Tri(n‐butyl)methylammoniumdodecaiodo‐tribismutate By reaction of equivalent amounts of BiI3, KI and I2 in [N(CH3) (n‐C4H9)3][N(SO2CF3)2] as Ionic Liquid, transparent reddish crystals with the composition [N(CH3)(n‐C4H9)3]3[Bi3I12] are formed. Concerning to X‐ray diffraction investigations based on single crystals as well as powders, [N(CH3)(n‐C4H9)3]3[Bi3I12] crystallizes monoclinic (P21/c; a = 2383.0(5); b = 1241.0(3); c = 2493.0(5) pm; β = 97.50(3)°; Z = 4). The anion consists of distorted (BiI6)‐octahedra, which are face‐shared via cis‐oriented octahedral faces. With the cis‐[Bi3I12]3?‐anion such a connectivity is firstly described. 相似文献
352.
B. Wolff H. Rottke D. Feldmann K. H. Welge 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,10(1):35-43
The interaction of hydrogen atoms with strong laser fields at intensities up to some 1013 W cm?2 was studied experimentally at the wavelengths λ=355 nm, 532 nm and 1064 nm. The ion yield, the energy spectrum of the photoelectrons and their angular distributions were measured. The angular distributions at λ=355 nm and λ=532 nm provide a sensitive test for theoretical calculations. Comparison with the calculations available shows that perturbation theory with proper inclusion of atomic structure yields results which agree with experiment. Intensity dependent changes of angular distributions at λ=532 nm are observed, which indicate that at 1013 W cm?2 higher order processes become noticable. At λ=1064 nm the situation is more complicated, experimentally as well as theoretically. Intensities of some 1013 W cm?2 are necessary to observe ionization. Strong distortions of the atomic structure can be expected. Presently only qualitative aspects of the angular distributions can be discussed. 相似文献
353.
By reacting Mn2(CO)10 and TeI4 in the ionic liquid[BMIm][OTf] (1‐butyl‐3‐methylimidazolium trifluromethanesulfonate), brick‐red crystals of [BMIm][(Te2)3{Mn(CO)3}2{Mn(CO)4}3]are obtained. The title compound contains the carbonyl anion[(Te2)3{Mn(CO)3}2{Mn(CO)4}3]–. Herein, three formal Te22– units and two formal Mn(CO)3+ fragments establish a distorted heterocubane‐like Te6Mn2 structure. Three edges of this heterocubane are furthermore capped by Mn(CO)4+ fragments. The resulting Te6Mn5 building unit, moreover, looks very similar to the P113– anion – the so‐called ufosane. The mean distances Te–Te and Te–Mn are observed with 277.6 and 264.7 pm, respectively. In addition to single‐crystal structure analysis, the title compound is characterized by infrared spectroscopy (FT‐IR), thermogravimetry (TG) and energy‐dispersive X‐ray (EDX) analysis. 相似文献
354.
J. Danon S.V. Filseth D. Feldmann H. Zacharias C.H. Dugan K.H. Welge 《Chemical physics》1978,29(3):345-351
The photodissociation of ketene, CH2CO(X?1A1) → CH2 (ã1A1) + CO(X 1Σ+) has been observed at 337 nm, using a pulsed nitrogen laser. The CH2 (ã 1A1) radical has been detected by laser induced fluorescence with a tunable dye laser. A laser excitation spectrum has been obtained from CH2(ã 1A1) over the wavelength interval from 588.9 to 595.6 nm in the Σ ← Π vibronic subband of the CH2 (ã 1A1); υ″ = 0, 0, 0?b? 1B1; υ′ = 0, 14, 0) transition. For the CH2(ã 1A1 ; υ′= 0, 0, 0?X? 3B1; υ′' = 0, 0, 0) energy separation an upper limit of (6.3 ± 0.8) kcal/mole has been found. The radiative lifetime τ and the rate constant k for the removal of the 000 rotational level of the Σ(0, 14, 0) vibronic state have been measured directly. The values are τ = (4.2 ± 0.2) μs and k = (7.4 ± 0.3) × 10?10 cm3 molecule?1 s?1, respectively. 相似文献
355.
356.