We investigated the electronic and structural properties of graphene layers grown on a 6H-SiC (Si-terminated) substrate by using core level photoemission spectroscopy (CLPES), low energy electron diffraction (LEED), and near edge x-ray absorption fine structure (NEXAFS). The angle between the plane of the graphene sheet and the SiC substrate was measured by monitoring the variation of the π * transition in the NEXAFS spectrum with the thickness of the graphene layers. As the thickness of the graphene layers increased, the angle gradually decreased.

We have measured W 4f 7/2 core-level photoemission spectra from W(110) in the presence of Ni overlayers, from ∼0.2 to ∼3 monolayers. Interfacial core-level shifts associated with first-layer Ni phases have been identified: −230 ± 15 meV for the 1×1 pseudomorphic phase and −70 ± 7 meV for the 7×1 close-packed commensurate phase. At higher Ni coverages the interfacial core-level shift is −100 ± 10 meV. These shifts are analyzed using the partial-shift model of Nilsson et al. [Phys. Rev. B 38 (1988) 10357]; the analysis indicates that the difference in binding energies between the 1×1 and 7×1 phases has a large contribution from structural differences between the two phases.

We have investigated atomic structure and electrical properties of the Au/ Si͑557͒-1 ϫ 2 surface by using scanning tunneling microscopy. We observe the doubled periodicity ͑ϫ2͒ for the step-edge atoms even far away from defects at room temperature ͑RT͒, indicating no Peierls-type transition reported earlier. We further identify the Au atoms well resolved from Si atoms in the Au-Si-Au chain at RT, in good accord with the prevailing structural model. Our scanning tunneling spectroscopy data taken along the step-edge atoms unambiguously reveal that these step-edge Si atoms are metallic, and are buckled apparently with a charge transferred from down to up Si atoms. We find no significant thermal fluctuation of the buckled step edges at RT.

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