| Abstract
| - We carried out Monte Carlo simulations of gold nanocrystals (NCs) and (111) slabs covered with alkyl thiols,with and without explicit solvent (n-hexane), at T = 300 K. Adsorption isotherms for propane- and octanethiolshowed a phase behavior measured previously in experiments. Comparison of the adsorption isotherm ofoctanethiol in hexane on a (111) slab with experimental data suggests that, in this system, no thiolate bondwas formed. The geometry of a gold surface strongly influences the formation and structure of the cappingmonolayer. On a (111) surface, attractive interactions between carbon chains are more pronounced than ona NC. This leads to a stronger penetration of the capping layer by the solvent. Adsorption selectivity forbinary alkyl thiol mixtures is stronger in vacuum than in solution. The convex shape of the NCs also reducesthe adsorption selectivity of binary thiol mixtures. This result shows that the solvent cannot be ignored insimulations.
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