Atomic-Level Understanding of Contact Potential of Quartz Surface

Laboratory and field observations have suggested a correlation between contact dynamics and slow dynamics. The underlying mechanical mechanisms at the contact level require investigation at the nanoscale. This study uses molecular dynamics (MD) simulations to investigate the interactions between two quartz plates separated by a water film, focusing on the relationship between adhesion force and separation distance. The density and orientation angle profiles were calculated from simulation data to investigate the relationship between the interfacial structure of the water film and contact potential. The simulations reveal multiple metastable states of the contact potential, consistent with existing theoretical models. The results show that the contact force is influenced by the structure of the water film, including oscillation forces and stratification. This provided verification and development for existing theoretical models based on metastable contacts.