Surface-electronic structure of La(0001) and Lu(0001)
  Most spectroscopic methods for studying the electronic structure of metal surfaces have the disadvantage that either only occupied or only unoccupied states can be probed, and the signal is cut at the Fermi edge. This leads to significant uncertainties, when states are very close to the Fermi level. By performing low-temperature scanning tunneling spectroscopy and ab initio calculations, we study the surface-electronic structure of La(0001) and Lu(0001), and demonstrate that in this way detailed information on the surface-electronic structure very close to the Fermi energy can be derived with high accuracy. 
D. Wegner, A. Bauer, Yu. M. Koroteev, G. Bihlmayer, E. V. Chulkov, P.   M. Echenique, and G. Kaindl