Simulations of Wearless Friction at a Sliding Interface between Ordered Organic Monolayers

Molecular dynamics and simple phenomenological simulations are used to model the friction between two ordered monolayers of alkane chains bound at their ends to rigid substrates. Results of calculations using these methods suggest that the frictional properties at a sliding interface between the ordered films are governed by two simplified potentials. One is a potential due to the lateral collective deformation of a film and the other is a corrugated interfacial potential between films facing each other. These two potentials are closely related to the nature of the films, i.e., their physical and chemical properties. In addition, the simplified models can be greatly extended to clarify the frictional behavior of other weakly interacting interfaces such as hydrogen-terminated diamond surfaces.