Band dispersion and empty electronic states in solid<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">C</mml:mi></mml:mrow><mml:mrow><mml:mn>60</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>: Inverse photoemission and theory

Abstract

Inverse-photoemission studies of the empty electronic states of solid ${\mathrm{C}}_{60}$ show ten features within 15 eV of the lowest empty state. Pseudopotential calculations identify the character of the empty states. Band calculations for fcc ${\mathrm{C}}_{60}$ demonstrate that dispersion of some of the states, due to intermolecular interaction, reproduces experimental results. Intensity variations of experimental features with incident electron energy reflect their \ensuremath{\pi} and \ensuremath{\sigma} character as well as their symmetries. Resonant coupling is observed between the inverse-photoemission decay channel involving the third feature and the radiative decay of a plasmon.