O. Hadjar et al., Projectile atomic-number effect on ion-induced fragmentation and ionization of fullerenes - art. no. 033201, PHYS REV A, 6303(3), 2001, pp. 3201
The delocalized pi electrons of a C-60 cluster can be well described as an
electron gas. Electronic friction experienced by a multicharged ion collidi
ng with a fullerene might then be modeled in terms of the electronic stoppi
ng power. We investigated such collisions for projectile atomic numbers Z r
anging from 2 to 18 and charge states q=2,3. Direct mass-spectrometric evid
ence of the clear oscillatory behavior of electronic-stopping-related proce
sses such as multifragmentation and ionization of C-60 was observed as a fu
nction of Z. From the positions of the maxima of the corresponding cross se
ctions, two classes of trajectories can be distinguished: close collisions
through the high electron density of the cage inducing multifragmentation,
and glancing collisions through the lower electron densities of the fullere
ne ''atmosphere'' inducing direct ionization.