Surface resistivity of semi-infinite crystals

The surface resistivity of low-index surfaces of Al is evaluated by a first-principles density-functional calculation. Contrary to the naive expectation that the close-packed (111) surface of fee metals would scatter conduction electrons in the metal nearly specularly, the calculated resistivity of Al(111) is found to be much larger than that of the more loosely packed Al(001) surface. The large difference between the two surfaces is not related to the strength of the surface scattering potential. Instead, it simply arises from the fact that the fee crystal has no reflection symmetry about the (111) crystal plane, which means that then is in general no Bloch wave corresponding to specular reflection when a conduction electron in the metal is incident on the (111) surface. [S0163-1829(98)00908-4].