Monte Carlo simulations of the underpotential deposition of metal layers on metallic susbtrates: Phase transitions and critical phenomena.

CECILIA GIMÉNEZ, M; M LEIVA, E P; EZEQUIEL V ALBANO

Modern Aspects of Electrochemistry.

Springer Verlag

Lugar: Heildelberg; Año: 2008; p. 1 - 100

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The adsorption of a metal monolayer or submonolayer for the systems Ag/Au(100), Au/Ag(100), Ag/Pt(100), Pt/Ag(100), Au/Pt(100), Pt/Au(100), Au/Pd(100) and Pd/Au(100) was studied by means of lattice Monte Carlo simulations. It was found that for some systems, the adsorbate atoms successively occupy kink sites, step sites and the complete monolayer. On the other hand, for other systems, we observe 2-D alloys between substrate and adsorbate-type atoms. In particular, based on the fact that the underpotential deposition of Ag atoms on the Au(100) surface exhibits sharp first-order phase transition at well defined values of  the (coexistence) chemical potential (mu_{coex}), we have also performed extensive simulations aimed to investigate the hyteretic dynamic behavior of the system close to coexistence upon the application of a periodic signal.