Abstract :
The (0001) surface of α-Mo2C has been studied using low-energy electron diffraction (LEED), X-ray photoelectron spectroscopy and angle-resolved photoelectron spectroscopy. When the ion-bombarded (1 keV of Ar+) surface is annealed at 1600 K, a C-rich MoC-like surface is formed. The surface gives a complex LEED pattern composed of (1×1) orthorhombic spots, (2×2)R15° spots, and (4/3×4/3)R5° spots. Photon energy dependence of the normal-emission spectra is measured and it is found that the spectrum in the valence band region consists of Mo 4d band, Mo 4d–C 2p hybrid band, and C 2s band. Any peaks associated with surface states are not found.
