One-dimensional commensurability and conduction-band dispersion in heteroepitaxialC60on GeS

The natural one-dimensional corrugation of the (001) cleavage plane of GeS, together with favorable lattice matching, allow the successful growth of oriented ${\mathrm{C}}_{60}$(111) fullerite layers, as evidenced by sharp low-energy electron diffraction patterns. ${\mathit{k}}_{\mathrm{\parallel }}$-resolved inverse photoelectron spectroscopy reveals small dispersion effects in the conduction bands of epitaxial multilayers at 300 K. Enhanced dispersion bandwidths are observed at room temperature for one ${\mathrm{C}}_{60}$ monolayer, indicating stronger bonding at the interface.