Partial densities of states of alloys:Cu3Au

The photon-energy dependence of the photoelectric cross section of the 4d and 5d elements is sufficiently strong to allow the isolation of the partial densities of states of many alloys and intermetallic compounds. For photon energies above 150 eV the valence-band spectra of ${\mathrm{Cu}}_3$Au are dominated by bulk and surface Cu 3d states. At photon energies below 50 eV the spectra correspond very closely to the d-band density of states of the surface Au atoms. X-ray photoelectron spectra at normal takeoff angle contain approximately equal contributions from bulk Au and Cu d states.