Single-particle and collective degrees of freedom in C60

Abstract
The electromagnetic response of the fullerene C60 in the energy range 0<or=E<or=35 eV, exhausting 84% of the Thomas-Reiche-Kuhn sum rule, has been worked out using the local density and random phase approximations. A detailed correspondence between the calculated pi -plasmons and the peaks determined in optical/UV studies is found. The damping width ( approximately=12 eV) of the Mie resonance observed at approximately=20 eV is well reproduced, and is due to Landau damping. This resonance is found to be determined by sigma to sigma and, to a large extent, also by sigma to pi , delta particle-hole transitions.