Photoabsorption of the fullerene C₆₀ and its positive ions

Abstract

The electronic structures and the total photoionization cross sections of the fullerene C60 and its positive ions C60 n+ (n=1, 2, 3) are calculated for the photon energy range from the ionization thresholds up to 80 eV and compared with the recent experimental data and other calculations. The theoretical approach is based on the local density approximation, the random phase approximation and the jellium models. In contrast to the previous studies, the Perdew–Wang parametrization for the exchange-correlation energy functional is used at present, which leads to more accurate electronic structures and cross sections. Two jellium models are thoroughly tested: the sphere jellium model and the spherical layer jellium model with a finite thickness. It is shown that the spherical layer jellium model provides more reliable results than the sphere model. Two giant resonances are found in the photoionization spectra of all fullerenes treated. The position and the shape of the resonances are determined in agreement with the experimental data.

Numerical Simulation of Charged Fullerene Spectrum

“…The model above provides a rather simplified description in the sense that it does not take into account the actual physical structure of a fullerene. A more realistic single-electron potential U (r) can be constructed in the framework of the jellium model [4,5,15] as a sum of the positive contribution of the carbon atom's nuclei located on the spherical surface of the fullerene radius R and the negative contribution of the electron clouds. The resulting potential is attractive and it has a cusp-shape form with the clear localization in the thin spherical shell.…”

New applications of the jellium model for the study of atomic clusters

“…The advantage of such approaches is that they allow one to overcome significant computational difficulties but at the same time take into account the essential features of the processes providing clear physical insight into the phenomena. During the last decades the jellium model have been applied frequently to the description of ground-state properties of fullerenes [34], as well as to the investigation of photoexcitation processes arising in these systems [12,[35][36][37][38].…”

Atomic cluster collisions

“…Delocalized electrons of the system, moving in the field created by the uniform positive charge distribution, are considered within either the self-consistent Hartree-Fock (HF) or the local density (LDA) approximations. The jellium model was applied frequently to the description of ground state properties of metal clusters and fullerenes as well as to the investigation of photoexcitation and electron scattering processes in these systems (see, e.g., [32][33][34][35][36][37][38][39] and Ref. [28] for earlier references).…”