THE ELECTRONIC-STRUCTURE OF THE CONDUCTION-BAND OF K3C60 STUDIED BY PHOTOEMISSION AND ELECTRON-ENERGY-LOSS SPECTROSCOPY

Temperature-dependent photoemission spectra of the conduction band of superconducting K3C60 confirm an earlier observation of a continuous transfer of spectral weight from the Fermi level (E(f)) to higher binding energies with increasing temperature. This suggests the occurrence of a metal to non-metal transition at elevated temperatures. Electron energy-loss spectroscopy (EELS) in transmission measurements of the conduction band plasmon of K3C60 show negligible dispersion as a function of the momentum transfer (q), thus deviating from the behaviour expected for a simple metal and from some recent theoretical predictions.