Optical response of C$_{60}$ and C$_{70}$ fullerenes:

TL;DR

This study models the optical responses of C60 and C70 fullerenes considering exciton effects, Coulomb interactions, and disorder, revealing how doping alters Coulomb parameters and absorption features.

Contribution

It introduces a comprehensive tight binding model incorporating long-range Coulomb interactions and bond disorder to analyze fullerene optical spectra.

Findings

Coulomb parameters are about half in doped versus neutral fullerenes.

Bond disorder effectively simulates peak broadening in spectra.

Doped fullerenes show significant changes in optical response.

Abstract

Molecular exciton effects in the neutral and maximally doped C$_{60}$ (C$_{70}$) are considered using a tight binding model with long-range Coulomb interactions and bond disorder. By comparing calculated and observed optical spectra, we conclude that relevant Coulomb parameters for the doped cases are about half of those of the neutral systems. The broadening of absorption peaks is well simulated by the bond disorder model.