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Surface chemical reactions oscillatory behavior

These models consider the mechanisms of formation of oscillations a mechanism involving the phase transition of planes Pt(100) (hex) (lxl) and a mechanism with the formation of surface oxides Pd(l 10). The models demonstrate the oscillations of the rate of C02 formation and the concentrations of adsorbed reactants. These oscillations are accompanied by various wave processes on the lattice that models single crystalline surfaces. The effects of the size of the model lattice and the intensity of COads diffusion on the synchronization and the form of oscillations and surface waves are studied. It was shown that it is possible to obtain a wide spectrum of chemical waves (cellular and turbulent structures and spiral and ellipsoid waves) using the lattice models developed [283], Also, the influence of the internal parameters on the shapes of surface concentration waves obtained in simulations under the limited surface diffusion intensity conditions has been studied [284], The hysteresis in oscillatory behavior has been found under step-by-step variation of oxygen partial pressure. Two different oscillatory regimes could exist at one and the same parameters of the reaction. The parameters of oscillations (amplitude, period, and the... [Pg.434]

The kinetics of chemical reactions on surfaces is described using a microscopic approach based on a master equation. This approach is essential to correctly include the effects of surface reconstruction and island formation on the overall rate of surface reactions. The solution of the master equation using Monte Carlo methods is discussed. The methods are applied to the oxidation of CO on a platinum single crystal surface. This system shows oscillatory behavior and spatio-temporal pattern formation in various forms. [Pg.737]

Chemical wave patterns corresponding to moving surface concentration patches are the result of coupling of siuface diffusion, surface reconstruction, and surface reaction. Depending on the reaction condition, such spatio-temporal phenomena can also lead to an oscillatory behavior of... [Pg.184]


See other pages where Surface chemical reactions oscillatory behavior is mentioned: [Pg.286]    [Pg.388]    [Pg.240]    [Pg.340]    [Pg.160]    [Pg.326]    [Pg.12]    [Pg.219]    [Pg.51]    [Pg.478]    [Pg.248]   
See also in sourсe #XX -- [ Pg.388 , Pg.404 , Pg.415 ]




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