Abstract:
The modern quantum-mechanical theory of the fundamental step in electrode reactions, which takes into account the necessity for the reorganisation of the polar medium and the qualitative difference between the behaviour of classical and quantum-mechanical degrees of freedom, is briefly reviewed. The experimental studies on the influence of various factors on the pre-exponential factor, the kinetic isotope effect, and the activation energy for the evolution of hydrogen have demonstrated a satisfactory agreement with the predictions of the quantum theory and a qualitative contradiction with the Horiuti–Polanyi model, which postulates the extension of the O–H bond in the activation process. The bibliography includes 50 references.