Preparation and Photoemission Spectra of Rb₃C₆₀ Single Crystal Thin Film

Rb₃C₆₀ single-crystal thin films were prepared on the cleaved (111) surface of C₆₀ single crystal. The photoemission spectrum line shapes of the lowest unoccupited molecular orbital (LUMO) derived band at room temperature and 150 K were established by the synchrotron radiation photoemission spectrum measurements. The density of states near the Fermi level was distinctly affected by temperature. No less than six sub-peaks of the LUMO band were observed even at room temperature. The existence of so many sub-peaks offered the opportunities to analyses in more detail the orientational structure and the electron-Boson interactions of the narrow-band metallic Rb₃C₆₀.