Jahn-Teller Spectral Fingerprint in Molecular Photoemission:C60

Abstract

The hu hole spectral intensity for C60 → C + 60 molecular photoemission is calculated at finite temperature by a parameter-free Lanczos diagonalization of the electron-vibration Hamiltonian, including the full 8 Hg, 6 Gg, and 2 Ag 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.

Time-resolved photoelectron spectroscopy of low-energy excitations of 4×4 C60/Cu(111)

“…In fullerite the triplet exciton can only hop to the next molecule if the modified nuclear wave function hops as well. This was introduced by Kuzmany and coworkers [61] mentioned by Wang and coworkers [55] and later verified by Tosatti and coworkers [62]. This reduces the hopping rate and thus reduces the chance of the triplet exciton to be lost to the copper substrate [11].…”

Low-energy excitations of a linearly Jahn-Teller coupled orbital quintet

“…The average position of the two H states in the one-phonon multiplet is located above ω: this causes the characteristic signature of JT in molecular photoemission which was observed and discussed in Ref. 11. Note that no singular behavior is observed near α s and π−α s (vertical lines), in contrast to all quantities based on a classical treatment of the vibrations, such as those plotted in Figs.…”

“…Figures 15-17 illustrate in detail the general finding [11] that in the PES of dynamic JT system with weak to intermediate coupling, the "1-phonon line" splits into essentially two features, usually with most spectral weight in the upper peak, blue-shifted up to 30% higher energy than ω. The blue shift of the 1-phonon satellite is not specific to the h ⊗ (G + H) JT model.…”

“…In contrast, spectroscopic techniques can and do provide direct measurements of the JT vibronic spectrum. For example, molecular photoemission [18,19] was recently shown [11] to provide relatively detailed information on the low-lying part of the vibronic spectrum of C + 60 , especially in a specific symmetry sector [20]. A clean theoretical understanding of the general features of this vibronic spectrum is therefore desirable.…”

Hydrogenation of Fullerene C60: Material Design of Organic Semiconductors by Computation

“…The electronic structure of C + 60 has been investigated both experimentally and theoretically because of its electronic degeneracy [58,59] [61], and 71 meV [62]. The value of λ 0 h of C + 60 (D 5d ) was calculated as 74 meV.…”