Journal ArticleDOI
Ru L edge x‐ray absorption studies of the electronic structure of Ru3(CO)12 adsorption and the formation of Ru–Cu bimetallics on Cu(111)
T. K. Sham,Toshiaki Ohta,Toshihiko Yokoyama,Yoshinori Kitajima,M. Funabashi,Nobuhiro Kosugi,Hiroto Kuroda +6 more
TLDR
Ru L2,3 edge XANES (x-ray absorption near edge structure) together with AES (Auger electron spectroscopy) and LEED (low energy electron diffraction) studies of Ru3(CO)12 adsorbed on Cu(111) reveal the following: (a) Ru 3 CO 12 adsorbs molecularly on Cu (1) at low temperature (≲−50°) and upon electron bombardment, Ru3 CO 12 dissociates to form bare Ru aggregates which exhibit very broad Ru L 2,3 white linesAbstract:
Ru L2,3 edge XANES (x‐ray absorption near edge structure) together with AES (Auger electron spectroscopy) and LEED (low energy electron diffraction) studies of Ru3(CO)12 adsorbed on Cu(111) reveal the following: (a) Ru3(CO)12 adsorbs molecularly on Cu(111) at low temperature (≲−50°). (b) Upon electron bombardment, Ru3(CO)12 dissociates to form bare Ru aggregates which exhibit very broad Ru L2,3 white lines and featureless absorption in the XANES spectrum indicating that the Ru atoms are not well ordered on the Cu(111) surface. (c) Annealing of the bare Ru aggregates on Cu(111) at 450 °C results in the formation of Cu/Ru bimetallic clusters in which the Ru atoms are in the core and exhibit bulk‐like Ru L2,3 XANES while the surface is covered with Cu atoms. Analysis of the Ru L3 white line intensity indicates that charge redistribution in the Ru d band occurs upon the transformation from the bare Ru aggregates to the bimetallic Cu/Ru clusters on Cu(111).read more
Citations
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The rate constant in the kramers multidimensional theory and the saddle-point avoidance
TL;DR: A special case of the multidimensional Kramers problem, where the traditional picture of the barrier crossing is disrupted due to the friction anisotropy, is discussed, and the rate-controlling stage of the process is shown to change under certain conditions and the kinetics is determined by approaching the transition region instead of crossing this region.
Journal ArticleDOI
Activated rate processes in the multidimensional case. Consideration of recrossings in the multidimensional Kramers problem with anisotropic friction
TL;DR: In this paper, the multidimensional Kramers problem of particle escape from a potential well under the action of a random force is considered in the case when friction is highly anisotropic and the multi-dimensional potential is such that a particle can escape from the well at the expense of its motion along the fast coordinates only, with fixed value of a slow coordinate.
Journal ArticleDOI
Ruthenium-copper: a model bimetallic system for studies of surface chemistry and catalysis
TL;DR: In this article, the surface chemistry and catalytic properties of ruthenium-copper catalysts were investigated using X-ray photoelectron spectroscopy and extended Xray absorption fine structure.
Journal ArticleDOI
The decomposition and chemistry of Ru3(CO)12 on TiO2(110) studied with X-ray photoelectron spectroscopy and temperature programmed desorption
TL;DR: In this paper, the decomposition process of triruthenium dodecacarbonyl (Ru3(CO)12) was investigated using synchrotron-based high resolution photoemission spectroscopy and temperature programmed desorption (TPD).
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Preparation of epitaxial ultrathin RuO2–TiO2(110) films by decomposition of Ru3(CO)12
TL;DR: In this paper, it was shown that the RuO 2 -TiO 2 interface is non-reactive, in the sense that the titanium atoms of the substrate are not reduced by reaction with the incoming metal atoms.
References
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