Perturbation of particle velocity distribution in a bistable chemical system

Departure from Maxwellian particle velocity distribution induced by chemical reactions is studied in a bistable homogeneous system maintained out of chemical equilibrium. In the vicinity of the bifurcation associated with the coalescence of two stationary states, the dynamics of the system is very sensitive to small perturbations originating from the deformations of particle velocity distribution. An analytical approach of Boltzmann equations and microscopic simulations show that the perturbation of velocity distribution results in a significant deformation of the bifurcation diagram.