From results of a scanning-tunneling-microscopy study we show that, on Pt(100), (i) boundaries between different rotational domains of the hexagonal reconstruction only occur at steps and (ii) neither the step direction nor (iii) the orientation of the respective neighbored domain dictates the direction of the reconstructed domain. The domain-domain and domain-step interactions decrease in the same order; their magnitude and the activation energy for reorientation of domains is related to a structural transition of this surface at 1100 K.

• Received 1 July 1985

DOI:https://doi.org/10.1103/PhysRevLett.56.228