SciELO - Scientific Electronic Library Online

 
vol.15 issue2Preparation, X-ray structural studies and plant growth regulatory activity of methyl 6alpha,7beta-thiocarbonyldioxyvouacapan-17 beta-oateMass spectrometry of 1,2,5-oxadiazole N-oxide derivatives: use of deuterated analogues in fragmentation pattern studies author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Journal of the Brazilian Chemical Society

Print version ISSN 0103-5053

Abstract

NEVES, Rodrigo S.; MOTHEO, Artur J.; FERNANDES, Fernando M. S. Silva  and  FARTARIA, Rui P. S.. Monte Carlo simulation of the adsorption of phenol on gold electrodes: a simple model. J. Braz. Chem. Soc. [online]. 2004, vol.15, n.2, pp. 224-231. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532004000200011.

Canonical Monte Carlo simulations, at 298 K, of the adsorption of phenol in a dilute aqueous solution on gold electrodes, at the potential of zero charge, are presented. The results suggest that the process occurs in two distinct and successive steps. Adsorption starts with the phenol oxygen atom pointing towards the gold surface and the aromatic ring in a quasi-perpendicular orientation relative to the surface. This is followed by the reorientation of the aromatic ring to a parallel configuration. The effect of the solvent is analyzed through the calculation of the potential of mean force acting on phenol. Despite the simplicity of the model and the interaction potentials used in the simulations, the results are in good agreement with experimental observations, giving insight into the microscopic details of the adsorption process of phenol at low concentrations.

Keywords : phenol adsorption; gold electrode; Monte Carlo simulation; mean force potential.

        · abstract in Portuguese     · text in English     · pdf in English