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

Journal Article · Tue Jul 15 00:00:00 EDT 1980 · Phys. Rev., B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.22.581· OSTI ID:5164411

Mills, K A; Davis, R F; Kevan, S D; Thornton, G; Shirley, D A

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

• Research Organization: Materials and Molecular Research Division, Lawrence Berkeley Laboratory, Berkeley, California 94720
• OSTI ID: 5164411
• Journal Information: Phys. Rev., B: Condens. Matter; (United States), Vol. 22:2
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GOLD
ELECTRONIC STRUCTURE
PHOTOELECTRON SPECTROSCOPY
PLATINUM
CRYSTAL FIELD
D STATES
MEDIUM TEMPERATURE
POLARIZATION
SYNCHROTRON RADIATION
TEMPERATURE DEPENDENCE
BREMSSTRAHLUNG
ELECTROMAGNETIC RADIATION
ELECTRON SPECTROSCOPY
ELEMENTS
ENERGY LEVELS
METALS
PLATINUM METALS
RADIATIONS
SPECTROSCOPY
TRANSITION ELEMENTS
360104* - Metals &amp; Alloys- Physical Properties