We have carried out calculations of the electronic structure of the (100) surface for Li, Na, and Cs. Surface states, and the modification of the bulk states in the region near the surface, have been determined. The surface charge density has been calculated for Na. The ions are represented by Ashcroft local model pseudopotentials, screened by a modified Lindhard dielectric function. Our calculations involve the propagation matrix method, which is described in detail. The function and first derivative of a combination of evanescent waves and traveling waves in the bulk are matched, over a plane parallel to the surface, with evanescent waves from the vacuum.
