A new lattice-gas model for describing the adsorption-induced surface reconstruction process

In this work we present a new model for describing the adsorption-induced s urface reconstruction process. Different situations can be observed dependi ng on the characteristics of the metal-metal J, adsorbate-adsorbate epsilon and metal-adsorbate lambda interactions. Neglecting the adsorbate-adsorbat e interactions, an analytical treatment is performed which allows exact sol utions for the free energy of the system in each case. We calculate the gro und state and, by means of Monte Carlo simulations and finite-size scaling theory, we evaluate the critical temperature as a function of coverage, T-c (theta). The phase diagrams of the model are analysed and compared to exper imental findings. (C) 1999 Elsevier Science B.V. All rights reserved.