Photoemission study of the valence-band satellite of Ni(110)

The photon-energy (hν) dependence of the angle-integrated and angle-resolved photoemission from Ni(110) has been measured to investigate the valence-band satellite. Contrary to the earlier observations, we found that the satellite moves with hν. The satellite centroid is observed at ∼6.0 eV below the Fermi energy ($E_F$), away from the 3p-3d resonance, and at ∼6.8 eV in the region of the resonance. The difference spectra show that on resonance the highest-binding-energy part (at ∼7.3 eV) of the satellite is additionally enhanced. The results are discussed in terms of the singlet and triplet satellites.