![]() Continuum elastic theory revealed the importance of long-range elastic interactions in deeper layers of the herringbone reconstruction, but it lacks atomic details, such as the role of elbow dislocation that cannot be properly considered ( 19). The herringbone pattern has a much larger period length of ~30 nm ( 17, 18), which makes it impossible to explore using ab initio methods. Theoretically, ab initio methods have been used to study the simple 22 × 3 stripe reconstruction using four- to five-layer slab models with about 200 atoms in the primitive cell ( 14– 16). These elbows are active sites for absorbing heterogeneous metals, such as Ni and Co ( 4). ![]() ![]() Note that dislocations are formed at the elbows of the herringbone pattern during the reconstruction. (ii) The formation of stripe pattern mainly releases the tensile stress in Au top layer along the direction, and, according to continuum elastic theory ( 2), this stripe pattern is not stable and will further reconstruct into a herringbone pattern with periodic stress domains ( 3). This densification creates a slight surface corrugation of 0.2 Å on the surface, which is distinguishable by scanning tunneling microscopy (STM) imaging. S1) can be understood by a two-step process: (i) The top layer densifies into a so-called 22 × 3 stripe pattern by inserting an extra Au atom into an atomic chain every 22 lattice constants. The reconstruction from a pristine Au(111) surface to a herringbone pattern (fig. ![]() Although this tendency holds true for all metals, gold is the only one where the close-packed (111) surface reconstructs into a herringbone pattern under ambient conditions. The coordination number of atoms on a transition metal surface is lower than that in the bulk, which generally leads to tensile stresses in the pristine metal surface and a tendency for the surface to reconstruct and release tensile stresses ( 1). ![]()
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