Extinction properties of an isolated C60 molecule

We study the extinction spectra of an isolated C60 molecule, within the framework of the vector wave function method. Electronic excitations on the C60 molecule surface are modeled by an infinitesimally thin spherical layer of the σ and π electrons, which is described by means of the two-dimensional two-fluid model. Numerical results show that a strong interaction between the fluids gives rise to the splitting of the extinction spectra into two peaks in a quantitative agreement with the π and σ+π plasmon energies.