Angle-resolved photoemission determination of. lambda. -line valence bands in Pt and Au using synchrotron radiation

摘要: Angle-resolved photoemission spectra are reported for Au (111) and Pt in the photon-energy range 6 < or = h..nu.. 33 eV. Experimental dispersion relations along ..lambda.. were derived both crystals; comparison with relativistic augmented-plane-wave calculations showed generally good qualitative agreement, but quantitative disagreement of order a few tenths an Band energies tabulated; values at GAMMA GAMMA/sub 8/=3.55, 5.90, 7/=4.45 eV Au; 8/=1.40, 4.07, 7/=2.80 Pt. The s band is found to be ca. 1 (Pt) 0.5 (Au) less bound than theoretical prediction. Ligand field parameters presented samples: xi(5d)=0.71 +- 0.05 eV, 10Dq=1.22 xi(5d)=0.66 10Dq=1.78 systematics 10Dq noble metals discussed. polarization dependence was used assign initial-state symmetries empirically: bands 3, 5 show ..lambda../sub 6/ symmetry, 2, 4, 6, 4/+..lambda../sub 5/. Cooling crystal that ''s-p plateau'' due thermally insensitive indirect process, thermal diffuse scattering phonon-assisted inelastic processes contribute tomore » loss spectral contrast room temperature. Resonances intensity photon energy investigated assigned terms final-state structure.« less