Local strain analysis of the herringbone reconstruction of Au(111) through atomistic simulations

In this paper, the concept of local surface mismatch is introduced and calculated in the framework of the tight-binding second moment approximation. Within this concept, the local surface lattice parameter is calculated, taking into account the bonds of the surface atoms with the bulk ones. It is shown that the local surface lattice parameter depends on the relative range of the repulsive part of the potential with respect to the attractive one: the smaller this latter is, the greater the local surface lattice mismatch is. An illustration of the consequences of this concept is given in the case of the herringbone reconstruction of Au(111). A strong dispersion of the in-plane surface nearest-neighbor distances, spreading from 2.68 Angstrom at the kink positions to 2.86 Angstrom in the fcc regions, is reported. A similar dispersion is observed for the hydrostatic pressures. This dispersion explains the preferential nucleation phenomena on such a reconstructed surface.