ELECTRONIC-STRUCTURE OF THE (1X1) OXYGEN OVERLAYER ON TIC(111) - ANGLE-RESOLVED PHOTOEMISSION-STUDY

Angle-resolved photoemission spectroscopy with synchrotron radiation has been used to study the electronic state of oxygen adsorbed on a TiC(111) surface at room temperature. Oxygen is adsorbed dissociatively forming a (1 X 1) overlayer on the TiC(111) surface at saturation coverage. The band structure of the (1 X 1)-O overlayer is measured in the two symmetry directions; [21 1BAR](GAMMA MBAR) and [01 1BAR](GAMMA KBAR) of the TiC(111) surface. The binding energy of the O 2p(z)-derived band is always lower than those of the O 2p(x)- and O 2p(y)-derived bands throughout the surface Brillouin zone, indicating that the 2p(x) and 2p(v) orbitals are more important for the chemisorption bond formation.