Symmetrisation procedures for detailed balancing of classical energy transfer probabilities

In a few previous papers, we introduced a so-called fluctuation model accounting for inelastic effects in molecular energy transfers induced by collisions. This model resulted in «symmetrisation rules» to be applied to the classical expressions for energy transfer probabilities, so that the detailed balance principle is satisfied. In this paper, we show that these symmetrisation procedures can also be successfully applied to various nuclear and molecular model processes. The resulting expressions for the probabilities, penetrabilities or cross-sections here obtained are shown to display correct behaviours and are worthy to be compared with the corresponding exact QM results. The comparison demonstrates interesting conceptual improvement of the classical equations and confirms that the symmetrisation procedures—as well as the underlying fluctuation model—are of a somewhat general applicability in physics, ranging from inelastic processes to tunnelling phenomena.