Abstract: The surface state behaviors incorporated into an equivalent circuit of CdSe thin film electrodes have been studied in K₂SO₄ and Fe(CN)₆^3-/^4- solution. Surface state capacitances and resistances were evaluated by analysis of the equivalent circuit impedance in numerical Laplace transformation. The surface state mapping were presented. The results of the similarity of the energies distribution of surface state in both solution indicated that the surface states were bascially associated with the surface nature of CdSe thin film electrodes.

Key words: surface state, CdSe thin film electrode, impedance analysis, Laplace transformation