SURFACE ELECTRONIC-STRUCTURE OF THE NDB6(110) CLEAN SURFACE STUDIED BY ANGLE-RESOLVED PHOTOEMISSION SPECTROSCOPY

An angle-resolved photoemission study of the NdB6(110) clean surface h as been done in order to investigate in detail the surface electronic structure. From the dependence of the valence-band photoemission spect ra on the surface condition and the exciting photon energy, we found a dditional peaks corresponding to the surface states on the NdB6(110) s urface. These surface states are located at around 1.8 eV in binding e nergy. The dispersion relations of these surface states were determine d along the <(Gamma)over bar>-(M) over bar symmetry line in the surfac e Brillouin zone and it is found that the energy dispersion for the pr esent surface state is about 250 meV. From the photon energy dependenc e and the analogy of these observations with previous results for the LaB6(110) clean surface, it is concluded that the present surface stat es have the same specifications as those of the LaB6(110) surface and are ascribed to the B 2p dangling bonds of the surface B framework.