Trends in metal surface relaxation

New LEED (low-energy electron diffraction) results are reported for Fe{310} and Fe{210} surfaces, including multilayer relaxation of atomic planes both perpendicular and parallel to the surface. The structures of six different surfaces of iron are now known. A comparison of the results yields relaxation trends: top-layer relaxation is found to increase monotonically as the surfaces become more open; for the higher-index surfaces {211}, {310} and {210} "decay curves" of relaxation as functions of depth into the surface show a surface-independent decay length (the depth at which the crystal returns to a bulk-like arrangement) of approximately 2 Å. © 1984.