The work function depends on the configurations of atoms at the surface of the material. For example, on polycrystalline silver the work function is 4.26 eV, but on silver crystals it varies for different crystal faces as (100) face : 4.64 eV, (110) face : 4.52 eV, (111) face : 4.74 eV. Ranges for typical surfaces are shown in the table below.