Vacuum ultraviolet reflectivity of small gold clusters

We report on the reflectivity spectra of continuous (d=1000 A) and discontinuous (d=12, 25, 35, and 50 A) gold films evaporated onto fused quartz substrates, measured in the photon energy range 1535 eV using synchrotron radiation. The spectra of very thin films are attenuated and shifted predominantly towards higher energies relative to the bulk gold one. The shifts are explained in terms of a modification of the Au band structure induced by the contraction of the fcc nearest-neighbor distance. © 1985 The American Physical Society.