Adsorption of polar molecules at a wall: Monte Carlo simulations and integral equations

In this paper we investigate the influence of an angular-dependent adsorption potential on the structure of a dipolar hard sphere fluid in the vicinity of a hard wall. We report Monte Carlo (MC) simulation results for the density profile, the orientational structure, the polarization and the electrical potential profiles and make detailed comparisons with the theoretical results obtained from integral equations theories. We propose a new version of the reference linearized hypernetted chain approximation (RLHNC) which clears up its relation with the mean spherical approximation (MSA). Good agreement with MC results is reached when one takes as a reference system the dipolar fluid in the absence of adsorption potential.