A low-energy electron diffraction (LEED) crystallographic analysis has been undertaken to assess the lateral and vertical relaxations for the Cu(100)-(2×2)-S surface structure. The motivation was provided by the recent report with angle-resolved photoemission extended fine structure (ARPEFS) by Bahr et al. [Phys. Rev. B 35, 3773 (1987)]. It was found that the surface structure given by ARPEFS does not account well for the measured LEED intensity curves, although these curves can be reasonably accommodated by a structural model with components of relaxation in some opposite senses to those previously reported.

• Received 25 April 1988

DOI:https://doi.org/10.1103/PhysRevB.39.8000