Overlapping associating fluids with directional bonds in a bulk and near ahard wall: Monte Carlo study

Two models have been used in these Monte Carlo simulations: the original mo del with an angular-dependent associative interaction and a model with an a ngular-averaged potential, which is better suited For simulation and comput ationaly more efficient. We show that in the homogeneous case under the sam e conditions, both models yield a nearly identical interparticle structure, but with a slightly different degree of dimerization. This causes differen ces between these models in the local density distribution of monomers and dimers when ail inhomogeneity is present. though the resulting local total density distribution is found to be the same. The theoretical predictions b ased on Wertheim's theory of association are always closer to the simulatio n data For the model with the angular-averaged potential.