NEW-TYPE OF PERIODIC LONG-RANGE RESTRUCTURING OF ORDERED METAL-SURFACES INDUCED BY LATERAL ADSORBATE INTERACTIONS - IODIDE ON AU(110) ELECTRODES

A new form of long-range surface restructuring of Au(110) is reported, specifically for Au(110) in aqueous iodide electrolyte at high electrode potentials where an ordered iodide adlayer is present. In-situ scanning tunneling microscopy reveals the formation of periodic terrace strips paralleling the (110BAR) direction with widths, ca. 25-40 angstrom, that diminish as the surface potential is increased. The (1 x 1) substrate unit cell, however, remains unaffected. The restructuring is postulated to be due to dipole-dipole repulsive interactions destabilizing terrace sites distant from steps, and hence limiting the size of the substrate-adlayer domains.