Vibrational data on adsorbed anions contribute to the description of the electrochemical double layer as well as add to the physiochemical properties of the electrified surface. In this study, phosphoric acid is one of the best systems to monitor. In a previous study, it was discovered that the nature and geometry of the phosphate species is dependant upon applied potential. Using cyclic voltammetry and in situ FTIR spectroscopy, the adsorption of phosphate species on a single crystal platinum was studied. The pH range was between 1.03 and 12.7. With an increased potential on polycrystalli…