Photoemission Spectra for Liquid and Crystalline Au

Abstract

Photoemission energy distributions have been measured for liquid and crystalline Au using photon energies from 16.8 to 40.8 eV. The nature of optical excitations is observed to change from direct interband transitions to local or nondirect transitions upon passing from the crystalline to the liquid state. For liquid Au, we measure $d$ bands of width 6 eV, with an edge about 1.6 eV below the Fermi level $E_{\mathrm{F}}$ and two peaks in the optical density of states at 3.2 and 5.8 eV below $E_{\mathrm{F}}$.