Influence of self-consistent screening and polarizability contractions on interlayer sliding behavior of hexagonal boron nitride

The interlayer sliding behaviors of hexagonal boron nitride (h-BN) were investigated via a density functional theory approach with dispersion interaction included. It was found that the self-consistent screening effect (SCS) and the polarizability contractions had significant influences on London dispersion forces, which are responsible for not only the stacking modes but also for the sliding behaviors of h-BN. In consideration of the ionic characteristics of h-BN, surprisingly, the calculated dispersion force was found to dominate the electrostatic interaction along a minimum-energy sliding pathway and make a pronounced contribution (similar to 35%) to the barrier during the constrained sliding. This study demonstrates that the SCS and polarizability contractions play important roles in the sliding behaviors of h-BN and that the long-range dispersion interaction should be carefully treated, even in systems with ionic characteristics.