Electronic Structure of Fullerene Anions

TL;DR

This paper investigates how electron-phonon interactions influence the electronic states of fullerene anions, potentially leading to pairing effects similar to those in atomic nuclei, with implications for fulleride ion experiments.

Contribution

It introduces the impact of vibronic coupling on the electronic level ordering in fullerene anions, highlighting a possible pairing mechanism beyond Hund's rule.

Findings

Vibronic coupling can dominate Hund's rule in fullerene anions.

Level ordering may indicate on-ball pairing due to electron-phonon interactions.

Experimental results in fulleride solutions may reflect these effects.

Abstract

We study the electronic states of isolated fullerene anions C$^{n-}_{60}$ ($1\le n \le 6$) taking into account the effective interaction between electrons due to exchange of intramolecular phonons. If the vibronic coupling is strong enough such an effect may overwhelm Hund's rule and lead to an ordering of levels that can be interpreted as on-ball pairing, in a manner similar to the pairing in atomic nuclei. We suggest that such effects may be sought in solutions of fulleride ions and discuss recent experimental results.