Abstract: The method according to the invention includes choosing a reaction presumed reaction mechanism; selecting, for said mechanism, at least one first function characteristic of a thermokinetic property that is invariant with the periodic variation frequency of a control parameter influencing said reaction, the first characteristic function being calculated at least from first-order oscillation amplitudes of the concentration of at least one of the species involved in said reaction. The method includes calculating a plurality of values of the first characteristic function from first-order oscillation amplitudes obtained experimentally and analyzing the calculated values of the first characteristic function to determine whether the first characteristic function is constant based on the calculated values, and if the first characteristic function is constant, assigning the presumed mechanism to said reaction.