The reconstruction of Au(100) and Au(111) electrodes is lifted at sufficiently positive potentials. From capacity data the difference in surface energy for the reconstructed and the bulk-terminated surface can be obtained; this energy difference is much larger for Au(100) than for Au(111). For non- or weakly adsorbing electrolytes the interaction between the surface dipole and the double layer field or, equivalently, the surface charge, determines the lifting of the reconstruction. (C) 2004 Elsevier B.V. All rights reserved.