  Electronic and vibrational degrees of freedom in atom-cluster collisions are
treated simultaneously and self-consistently by combining time-dependent
density functional theory with classical molecular dynamics. The gradual change
of the excitation mechanisms (electronic and vibrational) as well as the
related relaxation phenomena (phase transitions and fragmentation) are studied
in a common framework as a function of the impact energy (eV...MeV). Cluster
"transparency" characterized by practically undisturbed atom-cluster
penetration is predicted to be an important reaction mechanism within a
particular window of impact energies.
