Comment to "Experimental Evidence of a Dynamic Jahn-Teller Effect in C60+"

TL;DR

This paper critiques recent experimental evidence suggesting a dynamic Jahn-Teller effect in C60+ by arguing that the observed spectral peaks are too widely separated for the proposed tunneling explanation to be valid.

Contribution

It challenges the interpretation of photoemission data as evidence for the dynamic Jahn-Teller effect in C60+ by providing a critical analysis of the spectral peak separations.

Findings

Spectral peak separations are too large for tunneling interpretation.

The data do not conclusively demonstrate the dynamic Jahn-Teller effect.

The critique questions the validity of previous experimental interpretations.

Abstract

A recent Letter reports photoemission data for the free C60 molecule, showing an interesting three-peak structure, presented as evidence of dynamic Jahn-Teller (DJT) effect in the C60+ ion. Those data constitute, along with earlier spectra by the Uppsala group, the best available piece of experimental evidence about the spectrum of a hole in fullerene. DJT must indeed affect the fivefold-degenerate h_u hole molecular orbital, but we contend that the energy separation of these three peaks is far too large for the proposed tunneling interpretation to be correct.