Jahn-Teller Spectral Fingerprint in Molecular Photoemission: C60

TL;DR

This paper calculates the molecular photoemission spectrum of C60 at finite temperature, revealing how Jahn-Teller coupling influences spectral features and matches experimental data.

Contribution

It introduces a parameter-free Lanczos diagonalization method to accurately compute the spectrum including full vibrational mode couplings.

Findings

Computed spectrum at 800 K matches experimental data

Energy separation of spectral features measures Jahn-Teller coupling strength

Method captures complex electron-vibration interactions in C60

Abstract

The h_u hole spectral intensity for C60 -> C60+ molecular photoemission is calculated at finite temperature by a parameter-free Lanczos diagonalization of the electron-vibration Hamiltonian, including the full 8 H_g, 6 G_g, and 2 A_g mode couplings. The computed spectrum at 800 K is in striking agreement with gas-phase data. The energy separation of the first main shoulder from the main photoemission peak, 230 meV in C60, is shown to measure directly and rather generally the strength of the final-state Jahn-Teller coupling.