Non-local effects in the macroscopic theory of Van der Waals and adhesive forces

The role of deviations from perfect screening in the Van der Waals interaction between two metal half-spaces a distance d apart is analyzed for a simple model. The interaction energy which is finite for d → 0 includes asymptotic corrections to the well-known d^?2 law. These corrections lead to a reduction of the order of 30 to 40% of the interaction in the vicinity of equilibrium distances for particle adhesion.