Photoelectric Work Function of a Copper Single Crystal for the (100), (110), (111), and (112) Faces

The electron work function was measured by the Fowler method for four faces of a copper single crystal. The crystal was cleaned by repeated cycles of ion bombardment and annealing at 700^ under ultrahigh vacuum conditions. With uncertainties of =0. 03 eV, the work functions were found to be ₁₁₀=4. 48 eV, ₁₁₂=4. 53 eV, ₁₀₀=4. 59 eV, and ₁₁₁=4. 94 eV.