We have calculated the electronic structure of Cu in the vicinity of t
he (100) surface. We used the relativistic SCF-LMTO-ASA method, within
a slab geometry and including the surface dipole terms. We find two s
urface states at the <(M)over bar -point>; the first lies about 0.2 eV
above the d-band continuum and the second lies within a spin-orbit ga
p near the top of the d-band continuum. Both states have been observed
experimentally and our calculated dispersion relations are in reasona
bly good agreement with the measurements. We have also carried out fir
st-principles photocurrent calculations using the layer-by-layer poten
tial functions and the spectra are in excellent agreement with previou
s photoemission measurements. Copyright (C) 1996 Elsevier Science Ltd.