Experimental Band Structure of Na

Abstract

Normal-emission angle-resolved photoemission data from Na(110) are presented. Two discrepancies between these data and the predictions of free-electron theory are observed. First, the occupied-band width is 2.5 eV, while theory predicts 3.2 eV. Second, the bands near the Fermi level appear to have been severely distorted, as could be produced by a charge-density wave oriented normal to the surface.