A method for determining the reaction mechanism of a reaction, in which at least one first reagent is transformed into at least one first product, the process including the following steps: carrying out a reaction to transform the first reagent into a first product under given experimental conditions, the reaction comprising the periodic variation at a given frequency of a control parameter influencing the reaction; scanning a plurality of given frequencies of periodic variations of the control parameter influencing the reaction; for each studied frequency, measuring a property representative of the concentration of at least one of the species under the effect of the periodic variation, to determine at least the first-order oscillation amplitudes (A 1sin, A 1cos) of the concentration. characterized in that the method further comprises the following steps: choosing a reaction presumed reaction mechanism; selecting at least one first function (F(ω)) characteristic of a thermokinetic property that is invariant with the oscillation frequency for said supposed reaction mechanism, the first characteristic function (F(ω)) being calculated at least from first-order oscillation amplitudes (A 1sin, A 1cos) of the concentration of at least said species; calculating a plurality of values of the first characteristic function (F(ω)) from first-order oscillation amplitudes (A 1sin, A 1cos) obtained experimentally for the plurality of frequencies of the periodic excitation described in the step; analyzing the calculated values of the first characteristic function (F(ω)) to determine whether the first characteristic function (F(ω)) is constant based on the calculated values; when the first characteristic function (F(ω)) is constant, assigning the presumed mechanism to said reaction. carrying out a reaction to transform the first reagent into a first product under given experimental conditions, the reaction comprising the periodic variation at a given frequency of a control parameter influencing the reaction; scanning a plurality of given frequencies of periodic variations of the control parameter influencing the reaction; for each studied frequency, measuring a property representative of the concentration of at least one of the species under the effect of the periodic variation, to determine at least the first-order oscillation amplitudes (A 1sin, A 1cos) of the concentration. choosing a reaction presumed reaction mechanism; selecting at least one first function (F(ω)) characteristic of a thermokinetic property that is invariant with the oscillation frequency for said supposed reaction mechanism, the first characteristic function (F(ω)) being calculated at least from first-order oscillation amplitudes (A 1sin, A 1cos) of the concentration of at least said species; calculating a plurality of values of the first characteristic function (F(ω)) from first-order oscillation amplitudes (A 1sin, A 1cos) obtained experimentally for the plurality of frequencies of the periodic excitation described in the step; analyzing the calculated values of the first characteristic function (F(ω)) to determine whether the first characteristic function (F(ω)) is constant based on the calculated values; when the first characteristic function (F(ω)) is constant, assigning the presumed mechanism to said reaction.