  The oblique impacts of nanoclusters is studied by means of Molecular Dynamics
and theoretically. In simulations we explore two models -- Lennard-Jones
clusters and particles with covalently bonded atoms. In contrast to the case of
macroscopic bodies, the standard definition of the normal restitution
coefficient yields for this coefficient negative values for oblique collisions
of nanoclusters. We explain this effect and propose a proper definition of the
restitution coefficient which is always positive. We develop a theory of an
oblique impact based on continuum model of particles. A surprisingly good
agreement between the macroscopic theory and simulations leads to the
conclusion, that macroscopic concepts of elasticity, bulk viscosity and surface
tension remain valid for nanoparticles of a few hundreds atoms.
