Adsorption of particles with non additive interactions on square lattice

PINTO O. A; RAMÍREZ-PASTOR A.J.; NIETO F. D.

San Carlos de Bariloche, Rio Negro

Workshop; IX Latin American Workshop on Nonlinear Phenomena; 2005

e present a Monte Carlo study of the adsorption process forparticles which interact by means of non additive coupling. Inparticular, we consider the case when the interaction energylinearly increases with the number of occupied nearest neighborsites. Such rules mimic the expected kind of interactions in knownexperimental problems with surface reconstruction. We describe andanalyze the behavior of thermodynamic quantities, such as theadsorption isotherms, isosteric heat, thermodynamic factor, etc., asa function of both temperature and coverage. Kinetic quantities,such as the surface diffusion coefficients are also treated. Wecompare, discuss and explain the main differences with the morestudied case where the interactions are additive. We also presentthe critical behavior of the system by means of a finite-sizescaling method. The phase diagram is discussed in terms of thedifferent ordered phases present in the problem. The influence ofthe phase diagram in the behavior of thermodynamic and kineticquantities is discussed. A mean field treatment is presented inorder to compare the numerical results.