The influence of aliphatic amines on the potential of the structural transition (hex) → (1 × 1) for Au (100) electrode

The impact of the aliphatic amines on the potential (E T) of the structural transition (hex) → (1 × 1) for Au (100) electrode was investigated. This potential was shifted to more negative values as the concentration of a given amine increased. As E T depends linearly on the log of the bulk concentration for each amine it was suggested to use this relationship for quantitative determination of the amines. Moreover, it was shown that the presence of amines reduced the stability range of the (hex) structure in the following sequence methylamine < ethylamine < propylamine < butylamine due to their increasing adsorbability. Furthermore, for a given concentration the introduction of each subsequent –CH2– group into the carbon chain of an amine is accompanied by the reduction of the stability range of ca. 23 mV.