Experimental energy bands of a rare-earth metal: Gd(0001)

We have determined energy bands of Gd metal at room temperature with the use of angle-resolved photoelectron spectroscopy with synchrotron radiation. Along the central sixfold axis of the Brillouin zone, we find the two critical points of the 6s,5dz2-type band (4- at EF-1.4 eV and 1+ at EF-2.8 eV) and a critical point of a final-state band (4- at EF+6.6 eV) in qualitative agreement with band calculations. At the zone boundary 5d states are observed along the ML line at about EF-0.35 eV corresponding to an L1 point. Unoccupied 4f states appear in the secondary-electron emission within 1.6 eV of the vacuum level. The work function of Gd(0001) is 3.30.1 eV. © 1983 The American Physical Society.