Adsorption of uracil on bismuth single crystal planes

Uracil adsorption at Bi(h k l) has been studied using impedance spectroscopy method. The limiting adsorption potential shift, Gibbs energy of adsorption - Δ G A ∘ and interaction constant values a in the Frumkin isotherm have been calculated and compared with the corresponding data for Hg [V. Brabec, S.D. Christian, G. Dryhust, J. Electroanal. Chem. 85 (1977) 389; V. Brabec, S.D. Christian, G. Dryhust, Biophys. Chem. 7 (1978) 253]. It was found that the values of | - Δ G A ∘ | increase in the order Hg < Bi ( 1 1 1 ) < Bi ( 0 1 1 ¯ ) , but the values of a are higher for Bi(h k l) compared with Hg [V. Brabec, S.D. Christian, G. Dryhust, J. Electroanal. Chem. 85 (1977) 389; V. Brabec, S.D. Christian, G. Dryhust, Biophys. Chem. 7 (1978) 253]. The values of the limiting adsorption potential shift are comparable for the Hg and Bi(h k l) electrodes.