Abstract: Both the dependence of relative change in reflectance on potential and the differential reflection spectra for Au electrode in both 0.1 mol/L NaFsolution and 0. 1 mol/L NaF, 0. 01 mol/Lpyridine solution have been measured respectively. The results show the a new band at 700 nm appeared after the surface atoms of the Au electrode were in a certain oxidized state during anodic polarization. It is assigned to charge-transfer band formed by the adsorbed pyridine molecules and the surface atoms of the Au electrode via the upper full ω-orbitals and the dangling bonds. The band was shiefted to 650 nm after the surface atoms of the Au electrode were in a higher oxidized state due to more anodic polarization.

Key words: Differential reflection spectrum, Adsorption of pyridine, Cold electrode