A Simple Statistical Mechanical Approach for Studying Multilayer Adsorption of Interacting Polyatomics

Details A Simple Statistical Mechanical Approach for Studying Multilayer Adsorption of Interacting Polyatomics A Simple Statistical Mechanical Approach for Studying Multilayer Adsorption of Interacting Polyatomics

2008-10-30

arxiv.org/abs/0810.5593v1

Physics

Condensed Matter

Materials Science

38 pages, 12 figures

Scientific paper

10.1016/j.susc.2009.02.008

A simple statistical mechanical approach for studying multilayer adsorption of interacting polyatomic adsorbates (k-mers) has been presented. The new theoretical framework has been developed on a generalization in the spirit of the lattice-gas model and the classical Bragg-Williams (BWA) and quasi-chemical (QCA) approximations. The derivation of the equilibrium equations allows the extension of the well-known Brunauer-Emmet-Teller (BET) isotherm to more complex systems. The formalism reproduces the classical theory for monomers, leads to the exact statistical thermodynamics of interacting k-mers adsorbed in one dimension, and provides a close approximation for two-dimensional systems accounting multisite occupancy and lateral interactions in the first layer. Comparisons between analytical data and Monte Carlo simulations were performed in order to test the validity of the theoretical model. The study showed that: (i) the resulting thermodynamic description obtained from QCA is significantly better than that obtained from BWA and still mathematically handable; (ii) for non-interacting k-mers, the BET equation leads to an underestimate of the true monolayer volume; (iii) attractive lateral interactions compensate the effect of the multisite occupancy and the monolayer volume predicted by BET equation agrees very well with the corresponding true value; and (iv) repulsive couplings between the admolecules hamper the formation of the monolayer and the BET results are not good (even worse than those obtained in the non-interacting case).

Affiliated with

Also associated with

No associations

Rating

A Simple Statistical Mechanical Approach for Studying Multilayer Adsorption of Interacting Polyatomics does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A Simple Statistical Mechanical Approach for Studying Multilayer Adsorption of Interacting Polyatomics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Simple Statistical Mechanical Approach for Studying Multilayer Adsorption of Interacting Polyatomics will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-456510