The surfaces of Al and Na are simple systems, but they show several important features like surface states and image resonances. Using the weighted density approximation within the density functional theory we are able to account self-consistently for image effects in the description of their electronic properties.
SIMPLE METAL-SURFACES AND IMAGE POTENTIAL STATES / F., Finocchi; Bertoni, Carlo Maria; Ossicini, Stefano. - In: VACUUM. - ISSN 0042-207X. - STAMPA. - 41:(1990), pp. 535-537.