Monte Carlo study of binary mixtures adsorbed on square lattices

• Published in: Surface science Vol. 606; no. 1; pp. 83 - 90
• Main Authors: García, G.D., Sánchez-Varretti, F.O., Bulnes, F., Ramirez-Pastor, A.J.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 2012; Elsevier
• Subjects: Adsorption isotherms; Binary mixtures; Computer simulation; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Equilibrium thermodynamics and statistical mechanics; Exact sciences and technology; Heat of adsorption; Isotherms; Lattices; Monte Carlo methods; Monte Carlo simulations; Phase diagrams; Physics; Surface chemistry; Surface thermodynamics; Adsorption isotherms; Surface thermodynamics; Monte Carlo simulations; Equilibrium thermodynamics and statistical mechanics; Monte Carlo methods; Thermodynamic model; Digital simulation; Square lattices; Statistical mechanics; Binary mixtures; Thermodynamic equilibrium
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/j.susc.2011.09.002

The monolayer adsorption of interacting binary mixtures on 2D square lattices has been studied through grand canonical Monte Carlo simulation in the framework of the lattice-gas model. The process has been monitored through total and partial isotherms and differential heats of adsorption corresponding to both species of the mixture. Repulsive lateral interactions between the adsorbed particles have been considered, resulting in a rich variety of structural orderings in the adlayer. At the end of this work, the phase diagram characterizing the transitions occurring in the system has been determined. A nontrivial interdependence between the partial surface coverage of both species was observed and discussed. ► Interacting A-B mixtures on square lattices were modeled by Monte-Carlo simulations. ► A nontrivial interdependence between the partial coverage of both species was found. ► The conditions for the occurrence of the so-called “mixture effect” were obtained. ► The complete phase diagram of the system was determined.