[en] Well-defined electrodes used in the in situ mode of operation should be ultra-high vacuum tested with respect to the surface symmetry and order. In the single-crystal program in their laboratory, they use Pt(111) electrode which is characterized by LEED/Auger spectroscopy and they exploit surface chemistry of iodine to preserve the proper surface crystallography in solution. Radiochemical measurements with such a prepared electrode will be reported and the career of iodine chemisorbed on platinum and other single-crystals of metals will be scrutinized. They will also present the most recent data obtained with single crystals of rhodium and with polycrystalline gold. Adsorption of pyridine and bisulfate anions on the gold electrode by radio-electrochemistry will be described and compared with equivalent measurements on platinum. Some preliminary radiochemical data with Au(111) may also be reported