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Rudolf Taube Jörg-Peter Gehrke Reiner Radeglia 《Journal of organometallic chemistry》1985,291(1):101-115
The reaction of the η3-allylbis(triarylphosphite)nickel(II) complexes with butadiene under chain propagation to give the polybutadienyl complex, [3-RC3H4Ni(P(OAr)3)2]PF6, was monitored by 31P NMR spectroscopy. In the case of the triphenylphosphite complex both the anti- and the syn-configuration could be identified by means of their different AB spectra. The anti-syn isomerization, the higher reactivity of the thermodynamically more stable syn-form, and the formation of the anti-structure as a result of each individual butadiene insertion step was also proved. From these observations an experimentally well-grounded mechanism of the trans regulation with the anti-syn isomerization as the rate-determining step could be derived for the first time. 相似文献
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Experimental data are presented for the angular dependence of the relative flux, the mean energy and the speed ratio of deuterium molecules desorbing from a Ni(111) crystal surface at a surface temperature of Ts = 1143 K and at sulphur coverages ranging between 30% and less than 2% of a monolayer.The angular flux distribution is sharply peaked in the forward direction (cosdθwith 3 ? d ? 5) and the mean energy 〈E〉 of the desorbate depends strongly on the desorption angle θ. For normal desorption is about 700 K higher than Ts and for glancing angles (θ = 80°) it decreases to about 400 K below Ts The results obtained on sulphur free and sulphur covered Ni(111) surfaces are compared with our former data on polycrystalline nickel. The main differences in the kinetic features can be ascribed to the surface roughness. Accordingly, the angular distributions of flux, mean energy, and speed ratio, which deviate strongly from the Knudson and Maxwellian law, do not seem to depend considerably on sulphur coverage and surface structure. A qualitative explanation for these deviations is presented using the principle of detailed balancing. 相似文献
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Rudolf Haag Daniel Kastler Ewa B. Trych-Pohlmeyer 《Communications in Mathematical Physics》1974,38(3):173-193
For an infinite dynamical quantum system idealized as aC*-algebra acted upon by time-translations automorphisms in an asymptotically abelian way, we propose to characterize equilibrium states by the three properties of stationarity, stability for local perturbations of the dynamics, and relative purity. We show that a state with these properties either gives rise to a one-sided energy spectrum or is a KMS- (i.e. essentially a limit Gibbs-) state. 相似文献
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