STEP PATTERNS ON VICINAL RECONSTRUCTED SURFACES

Step patterns on vicinal (2 X 1) reconstructed surfaces of noble metal s Au(110) and Pt(110), miscut towards the (100) orientation, are inves tigated. The free energy of the reconstructed surface with a network o f crossing opposite steps is calculated in the strong chirality regime when the steps cannot make overhangs. It is explained why the steps a re not perpendicular to the direction of the miscut but form in equili brium a network of crossing steps which make the surface to look like a fish skin. The network formation is the consequence of competition b etween the - predominantly elastic energy loss and entropy gain. It is in agreement with recent scanning tunnelling microscopy observations on vicinal Au(110) and Pt(110) surfaces.