摘要翻译:
我们给出了CO在含有不同结构区域的非均匀Pt(100)表面上吸附和催化氧化的模拟结果。这些区域是在复盖层由六角形的重构相转变为正方形原子排列的块状(1x1)相的过程中形成的。在本方法中,表面跃迁用非平衡双稳行为来解释。双稳区的特征是六方相和(1×1)相共存,并终止于一个临界分叉点,该分叉点位于(T_c~680K,P_c~10托)。由于涨落的增加,在这个尖点附近的高温高压下的行为应该与在超高真空条件下实验中典型观察到的滞回型行为有质的不同。在非均匀表面上,我们发现了一个以吸附质浓度的随机驻波为特征的非均匀振荡区域。由此产生的波面空间变形使我们能够更深入地了解Pt(100)表面不规则振荡的本质。
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英文标题:
《CO-activator model for reconstructing Pt(100) surfaces: local
microstructures and chemical turbulence》
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作者:
Natalia Pavlenko
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最新提交年份:
2008
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分类信息:
一级分类:Physics 物理学
二级分类:Statistical Mechanics 统计力学
分类描述:Phase transitions, thermodynamics, field theory, non-equilibrium phenomena, renormalization group and scaling, integrable models, turbulence
相变,热力学,场论,非平衡现象,重整化群和标度,可积模型,湍流
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一级分类:Physics 物理学
二级分类:Materials Science 材料科学
分类描述:Techniques, synthesis, characterization, structure. Structural phase transitions, mechanical properties, phonons. Defects, adsorbates, interfaces
技术,合成,表征,结构。结构相变,力学性质,声子。缺陷,吸附质,界面
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英文摘要:
We present the results of the modelling of CO adsorption and catalytic CO oxidation on inhomogeneous Pt(100) surfaces which contain structurally different areas. These areas are formed during the CO-induced transition from a reconstructed phase with hexagonal geometry of the overlayer to a bulk-like (1x1) phase with square atomic arrangement. In the present approach, the surface transition is explained in terms of nonequilibrium bistable behavior. The bistable region is characterized by a coexistence of the hexagonal and (1x1) phases and is terminated in a critical bifurcation point which is located at (T_c ~680 K, p_CO ~10 Torr). Due to increasing fluctuations, the behavior at high temperatures and pressures in the vicinity of this cusp point should be qualitatively different from the hysteresis-type behavior which is typically observed in the experiments under ultrahigh vacuum conditions. On the inhomogeneous surface, we find a regime of nonuniform oscillations characterized by random standing waves of adsorbate concentrations. The resulting spatial deformations of wave fronts allow to gain deeper insight into the nature of irregular oscillations on Pt(100) surface.
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PDF链接:
https://arxiv.org/pdf/708.284