Substrate-mediated and temperature-modulated long-range interactions between bromine adatom stripes on Cu(1 1 1)

Abstract

Understanding long-range adsorbate-adsorbate interactions on surfaces, such as halogens on metal surfaces, is important in the fields of electrochemistry, catalysis, and thin film growth. In this work, we computationally studied bromine (Br) stripe formations on Cu(1 1 1). These stripes are found to be surface-mediated and temperature-modulated; they are facilitated by BrCu bonding guided by self-patterning of Cu(1 1 1) surface frontier orbitals and by strain release induced stripe migration in a thermal bath. The calculated surface wave-functions in frontier occupied states show stripe-like electron distributions and thus the favorable sites of Br adsorption on Cu(1 1 1) are also stripe-like. The temperature effect is notable in that the thermal energy of 50 K easily dominates Br stripe gathering in (√3×√3)R30° structures. Corresponding electron stripes on the surface could be generated, widened, shrunk or removed depending on spacing changes of Br stripes, thus reflecting diverse and changeable formation features for dynamic patterns of adsorbates on Cu(1 1 1).