Determination of the Electric Field Intensities in a Mid-Infrared Spectroelectrochemical Cell Using Attenuated Total Reflection Spectroscopy with the Otto Optical Configuration

Abstract

The normalized mean-squared electric field intensities in a thin-layer spectroelectrochemical cell with the attenuated total reflection (ATR) optical configuration have been determined and are compared with those for the overlayer-ATR and normal ATR methods. The components of the system were ZnSe or Ge hemispherical internal reflection elements, a Au metal electrode, and water. The calculations were performed for two different values of the molar absorption coefficient for water, namely, k = 0.133 (at 1635 cm-1) and k = 0.010 (at 1885 cm-1). It was determined that the electric field enhancements in the overlayer-ATR cell can also be found in the thin-layer (TL) ATR cell. This is important in that the TL-ATR cell allows greater control over the surface properties of the chosen electrode material.