Quasi-chemical approach for adsorption of mixtures with non-additive lateral interactions

PINTO O. A; P.M. PASINETTI; A. J. RAMIREZ-PASTOR

APPLIED SURFACE SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2017 vol. 392 p. 1088 - 1096

0169-4332

The statistical thermodynamics of binary mixtures with non-additive lateralinteractions was developed on a generalization in the spirit of the lattice-gas model and theclassical quasi-chemical approximation (QCA). The traditional assumption of a strictlypairwise additive nearest-neighbors interaction is replaced by a more general one, namelythat the bond linking a certain atom with any of its neighbors depends considerably on howmany of them are actually present (or absent) on the sites in the first coordination shell ofthe atom. The total and partial adsorption isotherms are given for both attractive andrepulsive lateral interactions between the adsorbed species. Interesting behaviors areobserved and discussed in terms of the low-temperature phases formed in the system.Comparisons with Monte Carlo simulations are performed in order to test the validity of thetheoretical model