Orientational Ordering in Physisorbed Molecular Layers Induced by Surface Geometry and Confinement

摘要

Monte Carlo calculations are performed to study the orientational ordering of a model two-dimensional molecular admonolayer confined between two monatomic steps of a square substrate.Aside from the orientational influence of the substrate on the molecular axes,we show strong competition between the lateral interactions and the confinement potential due to the steps,which is responsible for more or less abrupt orientational transitions depending on the strength of the various interactions,the width of the confinement,and the temperature.An application to the adsorption of N_2 monolayer adsorbed on Cu/CuO stripe substrate is discussed.