ENERGY-TRANSFER IN COLLISIONS OF ALKALI-METAL CLUSTERS AND IONS

The electronic energy loss of a positively charged projectile passing through a sodium cluster is calculated by the semiclassical Vlasov met hod. The electron density before impact is obtained within the local-d ensity approximation in the jellium model. For the dynamical response, the Vlasov equations are solved by test particle discretization. The model gives the correct breathing mode and dipole Mie frequencies. The energy deposit is calculated as a function of projectile velocity, ch arge and impact parameter and is compared with theoretical and tabulat ed values for bulk sodium.