INVESTIGADORES
RAMIREZ PASTOR antonio Jose
artículos
Título:
Phase behavior of attractive k-mers on two-dimensional lattices: a study from quasi-chemical approximation.
Autor/es:
LONGONE P.; DÁVILA, M. V.; RICCARDO J. L.; RAMIREZ PASTOR A. J.
Revista:
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2013 vol. 1 p. 1 - 11
ISSN:
0929-5607
Resumen:
The phase behavior of attractive linear rigid k-mers on two-dimensional
lattices was studied by theoretical and simulation calculations in the
framework of the lattice-gas model. Combining (i) the analytical
expression for the partition function of non-interacting k-mers, and
(ii) a generalization of the classical quasi-chemical approximation
(QCA) in which the adsorbate can occupy more than one adsorption site,
the main thermodynamic functions of the system were explicitly obtained.
It was found that, for temperatures below a certain condensation
temperature, the system undergoes a first-order phase transition which
is observed as a clear discontinuity in the adsorption isotherms. The
transition was studied in detail by calculating the temperature-density
phase diagrams. Comparisons with analytical data from Bragg-Williams
approximation and Monte Carlo simulations were performed in order to
test the validity of the theoretical model. The results obtained allowed
us not only to analyze the effect of introducing the lateral
interactions by following the configuration-counting procedure of the
QCA, but also to discuss the consequences of choosing the
configurational factor associated to adsorption of non-interacting
k-mers from different models developed to treat the multisite occupancy
adsorption problem.