In situ video-rate scanning tunneling microscopy studies of the anion adlayer on Au(1 1 1) electrodes in sulfate containing electrolytes are presented that provide direct data on the structure and dynamics of the potential induced phase transition between the disordered adlayer and the ordered (root 3 x root 7) structure as well as of local transient structures in the disordered adsorbate phase Specifically strong correlations between adsorbates spaced at distances of root 3 Au surface lattice constants along the [1 1 (2) over bar] directions of the metal substrate are observed supporting the formation of a 1D (bi)sulfate network via hydrogen-bonding along this direction This network structure is in accordance with the rather slow adsorbate dynamics with residence times in the range of milliseconds or larger (C) 2010 Elsevier B V All rights reserved